Zodiac Medline Boats vs. Zodiac Open Boats: Which Model Is Right For You?

The Zodiac Medline boats and the Zodiac Open lineup are not two versions of the same boat brand. They are built for two genuinely different kinds of boaters, and choosing between them is less about which Zodiac RIB boat looks better and more about how seriously you use the water.

The Open series is Zodiac's recreational RIB range: lighter, more accessible, and designed for day trips, family outings, and inshore use. The Medline series is Zodiac's professional-grade RIB range: heavier, more capable, built for offshore conditions, extended range, and the kind of use that demands hydraulic steering, higher HP ceilings, and onboard comfort as standard.

This guide is built to help you self-select. By the end, you should know which Zodiac RIB boat series fits your boating style and which specific model within that series matches your crew size and conditions.

Open & Medline: Two Series, Two Different Boats

The most important distinction between the Medline and Open series is hull construction and what it enables. Both are RIBs with inflatable tube sets, but the similarities largely end there.

Zodiac Medline boats are built on a deeper, heavier fiberglass hull designed for performance at speed in open water. Every Medline model comes standard with hydraulic steering, a leaning post or bolster, and built-in fuel tanks sized for real range. These are not day-tripper tanks. The Medline range spans 5.8m to 9m, with HP ceilings from 130 to 450 HP, and the 9 accepts twin engines. This is a series built for buyers who take performance, range, and offshore capability seriously.

The Open series is built on a lighter hull with a more accessible price point and a feature set aimed at recreational use. Mechanical steering is standard across all four models. The 4.2 and 4.8 share a 46L portable fuel tank, the 5.5 and 6.5 step up to built-in 100L and 200L tanks respectively. HP ceilings run from 50 to 150 HP. This is a series built for buyers who want a well-equipped RIB for family use, calm inshore waters, and weekend outings without the complexity or cost of a professional-grade hull.

Quick Comparison of Zodiac Medline & Open at a Glance

Zodiac Medline Boats

Zodiac Open Boats

The Zodiac Open Boats: Built for the Weekend

The Open series is the right starting point for buyers who want a serious, well-built RIB without crossing into professional-grade territory. All four Zodiac Open models share the same core foundation, mechanical steering, navigation lights, and console setup. What changes as you move up the range is size, HP ceiling, fuel capacity, and onboard comfort.

Zodiac Open 4.2: The Entry Point

At 13'9" with a 50 HP ceiling and a 270 kg hull, the Zodiac Open 4.2 is the most accessible Zodiac RIB boat. It carries up to 6 people and runs on a 46L portable fuel tank, which suits the kind of short-hop inshore use this boat is built for.

Who it's for

New boaters, buyers upgrading from a smaller inflatable, families with younger children, and anyone operating in calm protected waters where a lightweight, easy-to-trailer boat is the priority.

Trade-offs to know

The inside length is just 8'10", the smallest usable cockpit in the range. The 46L tank limits range to short trips. At 50 HP max, this is not a performance boat. But within its intended use, it delivers cleanly.

Motor Pairing

Electric:

The Torqeedo Cruise 3.0 RS (6 HP equivalent, 3,000 W) is a clean fit for calm inshore use: quiet, zero emissions, and well-suited to harbour and bay boating where the 4.2's 50 HP ceiling is rarely needed in full.

Gas:

The Tohatsu MFS9.8C or Yamaha F9.9 sit comfortably within the 50 HP ceiling and give the 4.2 a capable everyday motor without overloading a lightweight hull.

Zodiac Open 4.8: More Room, Same Accessibility

The Zodiac Open 4.8 adds roughly 20 inches of length over the 4.2 and steps up to an 80 HP ceiling and 5 air chambers versus 3. The inside length grows to 9'7", giving you more usable cockpit space with the same crew capacity of 6.

Who it's for

Buyers who want the Open series entry point but need more room to move around and more outboard flexibility. The 80 HP ceiling gives you a meaningfully wider range of motor options compared to the 4.2.

Trade-offs to know

The 46L tank is the same as the 4.2, so range is still limited. The step up here is deck space and HP ceiling, not range or payload.

Motor Pairing

Electric:

The Torqeedo Cruise 6.0 TS (9.9 HP equivalent, 6,000 W) is the right electric step up, enough output for displacement-mode cruising on inshore waters, with tiller control suited to the boat's mechanical steering setup.

Gas:

The Tohatsu MFS9.8C is the natural pairing at the lower end. For buyers who want more output, the Yamaha F20 or Tohatsu MFS20E push toward the 80 HP ceiling and give the 4.8 genuine performance.

Zodiac Open 5.5: The Versatile Mid-Range

The Zodiac Open 5.5 is where the series makes a meaningful jump. At 18'8" with a 130 HP ceiling, 585 kg hull weight, 12-person capacity, and a built-in 100L fuel tank, this is no longer a short-hop boat. The standard equipment steps up significantly: tilting console, ski and wakeboard locker, modular aft seating with a 3-seat bench, bolster with integrated storage, and a 54L under-bench cooler. This is a proper day boat.

Who it's for

Larger families, water sports buyers, and buyers who want a RIB capable enough for a full day on the water with a crew. The ski and wakeboard locker and 130 HP ceiling make this the first Open model that genuinely handles tow sports.

Trade-offs to know

Mechanical steering is standard, hydraulic is an optional upgrade. If you're regularly running at the top of the HP range or in choppier conditions, the hydraulic steering upgrade is worth adding.

Motor Pairing

Gas only: At 130 HP max, this boat's primary use, water sports, full crew, sustained speed, requires gas. The Tohatsu MFS115A or Yamaha F115 are the strongest pairings, sitting well within the ceiling and well-matched to the boat's weight and intended use. For buyers who want headroom below the max rating, the Yamaha F90 or Tohatsu MFS90A are solid mid-range alternatives.

Zodiac Open 6.5: The Top of the Open Range

The Zodiac Open 6.5 scales the 5.5's platform to 21' with a 150 HP ceiling, 15-person capacity, and a built-in 200L fuel tank. The standard equipment mirrors the 5.5, with the same core layout: tilting console, ski and wakeboard locker, modular aft seating, bolster with storage, and under-bench cooler. The jump is in size, range, and crew capacity.

Who Zodiac Open 6.5 is for

Buyers who want the maximum the Open series offers, the largest crew capacity, the most range, and the highest HP ceiling in the range. This is also the model to consider if you want a RIB that can handle a longer day on the water without returning to fuel.

Trade-offs to know

At this size and HP ceiling, the Zodiac Medline 5.8 enters the conversation. The Zodiac Open 6.5 is lighter and more accessible, but the Medline 5.8 offers hydraulic steering as standard and a more capable hull for open water. See the crossover section below for a direct comparison.

Motor Pairing

Gas: The Yamaha F115 or Tohatsu MFS115A pair cleanly with the 6.5's 150 HP ceiling for everyday use. Buyers who want to run closer to the ceiling, particularly for water sports with a larger crew, should look at the Yamaha F150 or Tohatsu MFS140A, both within the rated limit.

The Zodiac Medline Boats Series, Built for More

The Medline series is Zodiac's professional-grade RIB lineup. Every model comes standard with hydraulic steering, a leaning post or bolster, and a hull built to handle conditions the Open series is not rated for. If you're buying a RIB to use it hard, take offshore, run at sustained speed with a full crew, or use commercially, the Zodiac Medline is the right series.

Zodiac Medline 5.8: The Entry Point Into Professional Grade

At 19' with a 130 HP ceiling and 673 kg hull weight, the Zodiac Medline 5.8 is the most accessible entry into the professional-grade RIB category. It carries 11 people (category C) and runs from a 100L built-in fuel tank. What sets it apart from the Open series immediately is hydraulic steering as standard, a leaning post, and a bow sunbathing area.

Who it's for

Buyers stepping up from a recreational inflatable who want fiberglass-hull performance and professional-grade build quality. Also suits buyers who need a capable yacht tender for a larger mother ship, or anyone regularly operating in conditions where a lighter recreational hull is not appropriate.

Trade-offs to know

The 5.8 shares a 130 HP ceiling with the Zodiac Open 5.5 and approaches the Zodiac Open 6.5's 150 HP ceiling. The difference is hull construction, standard equipment, and the conditions each boat is built for. If you are operating inshore in protected waters, the Zodiac Open 5.5 gives you comparable HP at lower weight and cost. If you need a hull that handles open water confidently with hydraulic steering as standard, the Zodiac Medline 5.8 is the right call.

Motor Pairing

Gas: The Yamaha F115 or Tohatsu MFS115A are the practical sweet spot, strong mid-range torque, well within the 130 HP ceiling, and proven on hulls of this size and weight.

Zodiac Medline 6.8: Performance and Comfort

The Zodiac Medline 6.8 is where the series makes a decisive jump. At 22'10" with a 250 HP ceiling, 950 kg hull, 14-person capacity, and a 200L built-in fuel tank, this is a boat built to cover serious ground with a serious crew. Standard equipment includes a rear U-lounge with two benches and folders, ski and wakeboard locker, self-bailing cockpit, easy access aft platforms, modern console with integrated bow seat platforms, and tilting bolster.

Who it's for

Experienced boaters who want genuine offshore performance, water sports capability, and onboard comfort. The 250 HP ceiling opens up twin-engine configurations, and the 200L tank gives you the range to use them.

Trade-offs to know

At 950 kg, the 6.8 is not a boat you trailer casually. It lives on a mooring, on davits, or in the water. If you need something you can tow to the water regularly, the 5.8 is the more practical choice.

Motor Pairing

Gas: The 250 HP ceiling opens up meaningful options. The Yamaha F200 or Tohatsu MFS115A are sensible single-engine pairings for everyday use. For buyers considering twin engines, twin Yamaha F115 or twin Tohatsu MFS115A sit well within the total HP envelope and deliver balanced performance.

Read Tohatsu vs Yamaha for Inflatable Boats to understand which outboard would work for you the best

Zodiac Medline 7.5: The Serious Performer

The Zodiac Medline 7.5 is the first model in the range that genuinely moves into day-cruiser territory. At 24'1" with a 300 HP ceiling, 1,150 kg hull, and a 300L fuel tank, it is built for extended offshore use. Standard equipment includes a double-position bolster with built-in kitchen, kit shower with sink faucet and fresh water tank, rear table and aft U-lounge, 3 large storage compartments, 2 swimming platforms with port telescopic boarding ladder, and a tilting console with under-deck storage.

Who it's for

Experienced offshore boaters, charter operators running day trips, and large family groups who want serious RIB performance alongside meaningful onboard comfort. The built-in kitchen and fresh water shower mean this boat supports extended time on the water, not just a run between anchorages.

Trade-offs to know

At 1,150 kg this is a serious vessel that requires proper mooring or berthing infrastructure. If you don't need the kitchen, fresh water shower, and extended offshore range the 300L tank provides, the 6.8 covers most use cases with less commitment.

Motor Pairing

Gas: The Yamaha F200 is the natural single-engine recommendation, strong output, well within the 300 HP ceiling for everyday use. Buyers running at the ceiling should look at the Yamaha F250 or Tohatsu MFS250, both stocked at Annapolis Inflatables. Twin Yamaha F150 is also a well-matched configuration for buyers who prefer twin-engine redundancy at this size.

Zodiac Medline 9: The Flagship

The Zodiac Medline 7.5 is the first model in the range that genuinely moves into day-cruiser territory. At 24'1" with a 300 HP ceiling, 1,150 kg hull, and a 300L fuel tank, it is built for extended offshore use. Standard equipment includes a double-position bolster with built-in kitchen, kit shower with sink faucet and fresh water tank, rear table and aft U-lounge, 3 large storage compartments, 2 swimming platforms with port telescopic boarding ladder, and a tilting console with under-deck storage.

Who it's for

Experienced offshore boaters, charter operators running day trips, and large family groups who want serious RIB performance alongside meaningful onboard comfort. The built-in kitchen and fresh water shower mean this boat supports extended time on the water, not just a run between anchorages.

Trade-offs to know

At 1,150 kg this is a serious vessel that requires proper mooring or berthing infrastructure. If you don't need the kitchen, fresh water shower, and extended offshore range the 300L tank provides, the 6.8 covers most use cases with less commitment.

Motor Pairing

Gas: The Yamaha F200 is the natural single-engine recommendation, strong output, well within the 300 HP ceiling for everyday use. Buyers running at the ceiling should look at the Yamaha F250 or Tohatsu MFS250, both stocked at Annapolis Inflatables. Twin Yamaha F150 is also a well-matched configuration for buyers who prefer twin-engine redundancy at this size.

Zodiac Open 6.5 vs. Medline 5.8, Where the Series Overlap

These two models will appear in the same search results and the same budget conversations, and it is worth addressing them directly. On paper they look similar: both are in the 19-21 foot range, both have HP ceilings around 130-150 HP, and both carry a crew of 11-15. But they are not the same boat.

The Zodiac Open 6.5 weighs 760 kg and comes with mechanical steering as standard. Its hull is built for inshore recreational use, and the 200L tank gives it solid range for day trips in protected waters. Hydraulic steering is available as an upgrade, but it is not the default.

The Zodiac Medline 5.8 weighs 673 kg and comes with hydraulic steering, a leaning post, and a GRP hull built for open water use. The lighter weight is the result of a different hull construction approach, not a less capable boat. The Zodiac Medline 5.8 is rated for conditions the Zodiac Open 6.5 is not.

The deciding question: where do you use the boat? If you are operating inshore in a bay, harbour, or protected coastal area, the Zodiac Open 6.5 gives you more deck space and a more recreational-focused feature set. If you are operating in open water, crossing bays, or regularly encountering chop and swell, the Medline 5.8 is the right hull.

Once you've settled on the hull, the next decision is tube material. Read Hypalon vs PVC to understand the difference before you buy.

Which Series Is Right for You?

The decision between Medline and Open comes down to where you boat, how you use it, and how seriously you push the boat.

• If you boat in protected inshore waters with a family crew and want an accessible, well-equipped RIB for day trips and water sports, choose the Open series.
• If you operate in open water, offshore, or in conditions that demand a professional-grade hull with hydraulic steering as standard, choose the Medline series.
• If you are undecided and operate primarily inshore but want room to grow, the Zodiac Open 5.5 or 6.5 with the hydraulic steering upgrade is the practical middle ground.

Within the Open series:

• Smaller crew, protected waters, new to RIBs: Zodiac Open 4.2 or 4.8
• Full family crew, water sports, day trips: Zodiac Open 5.5
• Largest crew capacity, extended day range, maximum Open capability: Zodiac Open 6.5

Within the Medline series:

• First professional-grade RIB, open water capable, yacht tender for a larger vessel: Medline 5.8
• Offshore performance, water sports at speed, extended range: Zodiac Medline 6.8
• Day-cruiser comfort with offshore performance, charter and family groups: Zodiac Medline 7.5
• Commercial, offshore, twin-engine, cabin: Zodiac Medline 9

View the Full Zodiac Range at Annapolis Inflatables

Annapolis Inflatable is an authorized Zodiac dealer serving the Chesapeake Bay region. We stock the full Open and Medline range and can help you match the right model to your boat, your crew, and your conditions. Contact our team or visit our store in Annapolis.