DUI vs Waterproof
FLX Extreme - DUI Drysuit vs D7X Nylotech
Shell or neoprene, seals and fit: which suit would we shortlist?
DUI
Waterproof
Scores are our editorial opinion of these models, based on features, suitability and ownership trade-offs—not hands-on test results. How we chose →
We’d pick the FLX Extreme - DUI Drysuit.
We’d start with DUI FLX Extreme - DUI Drysuit. We like FLX Extreme for its front entry and reinforced leg and knee areas. Choose Waterproof D7X Nylotech instead if its strengths are a better match: we like the D7X for a front-entry shell setup with replaceable silicone seals and expandable pockets.
Which one suits you?
DUI FLX Extreme - DUI Drysuit
We like FLX Extreme for its front entry and reinforced leg and knee areas. The separate FLX HD fabric option should not be confused with this version.
Get to know this model →Waterproof D7X Nylotech
We like the D7X for a front-entry shell setup with replaceable silicone seals and expandable pockets. Fit it over the intended undersuit and include the seal-system spares you want in the complete quote.
Get to know this model →Specifications side by side
The details that matter, side by side. “Check with the brand” means we have not confirmed that detail.
| Detail | DUI FLX Extreme - DUI Drysuit | Waterproof D7X Nylotech |
|---|---|---|
| Material | Polyester / butyl rubber / polyester trilaminate | Nylotech trilaminate |
| ReinforcementCheck with the brand | Cordura leg/knee overlays | Check with the brand |
| Entry | Diagonal front zip | Curved metal front zip with protective cover |
| FitCheck with the brand | Telescopic torso; internal waist adjustment | Check with the brand |
| Variant cautionCheck with the brand | FLX HD is a separate fabric option | Check with the brand |
| TorsoCheck with the brand | Check with the brand | Adjustable telescopic design |
| SealsCheck with the brand | Check with the brand | Silicone; Quick Neck and QCS Oval |
| StorageCheck with the brand | Check with the brand | Expandable zippered Power pockets |
Showing all 8 specification rows.
What the differences mean when you buy
Shell and construction
DUI FLX Extreme - DUI Drysuit
- Material
- Polyester / butyl rubber / polyester trilaminate
- Reinforcement
- Cordura leg/knee overlays
Waterproof D7X Nylotech
- Material
- Nylotech trilaminate
Compare the actual shell, reinforcement and lining rather than treating all trilaminates as equivalent. Denier, fabric mass and neoprene thickness measure different things. An integrated mesh lining changes the system being evaluated, but does not establish a universal exposure limit. Durability claims need suitable testing, not just a material name.
Entry, fit and boots
DUI FLX Extreme - DUI Drysuit
- Entry
- Diagonal front zip
- Fit
- Telescopic torso; internal waist adjustment
Waterproof D7X Nylotech
- Entry
- Curved metal front zip with protective cover
- Torso
- Adjustable telescopic design
Fit the suit over the undergarments intended for use and check reach, bending, boot fit and entry. A quoted weight applies to its named size and configuration; do not compare it with an unweighed made-to-measure order. Front and rear entry create different dressing requirements that should be tried before purchase.
Seals, pockets and ordered options
DUI FLX Extreme - DUI Drysuit
- Variant caution
- FLX HD is a separate fabric option
Waterproof D7X Nylotech
- Seals
- Silicone; Quick Neck and QCS Oval
- Storage
- Expandable zippered Power pockets
Write down the exact neck and wrist system, replacement parts and pocket configuration. Similar model names can use different rings and zippers. A field-replaceable seal system is useful only with the correct spares and knowledge; it does not make unrelated components interchangeable. Confirm current production changes and the options on your quotation.
A closer look at both
FLX Extreme - DUI Drysuit
The FLX Extreme is a polyester/butyl-rubber/polyester trilaminate drysuit with a thicker rubber layer than the TLS350 and Cordura overlays on the legs. Its diagonal front zip, telescopic torso and waist adjustment are intended to preserve movement while adding protection. DUI also offers an FLX HD fabric option, which should be specified separately.
What we like
We like FLX Extreme for its front entry and reinforced leg and knee areas.
What would make us think twice
The separate FLX HD fabric option should not be confused with this version.
More about the FLX Extreme - DUI Drysuit →D7X Nylotech
The D7X Nylotech is a front-entry trilaminate drysuit with a telescopic torso and a covered metal zipper. Its silicone seals use SI TECH Quick Neck and QCS Oval systems. The Nylotech fabric, expandable pockets and shaped boot arrangement make it a candidate for divers who want a fully equipped shell suit with replaceable seals.
What we like
We like the D7X for a front-entry shell setup with replaceable silicone seals and expandable pockets.
What would make us think twice
Fit it over the intended undersuit and include the seal-system spares you want in the complete quote.
More about the D7X Nylotech →Four checks before you place an order
- Arrange a full fitting over the intended undergarments, including boot and fin compatibility.
- Check the actual entry procedure and range of movement with qualified fitting assistance.
- Record the ordered seals, rings, zipper, boots, pockets and alterations in writing.
- Ask about suitable training, servicing, repair turnaround, replacement seals and warranty conditions.
Ask for a quote for the complete kit, including the accessories you need. That makes the price comparison much more useful.
Price, accessories and owning the equipment
Price the complete exposure system, including undergarments, any dry-glove arrangement, alterations and required spares. Made-to-measure and stock suits can have different delivery and return conditions. A base price comparison becomes misleading if one quote includes boots or seal systems that the other treats as options.
Changing suit construction should prompt a review of fit and equipment compatibility with qualified support. A drysuit comparison is not operational training. Follow the model’s zipper, seal and storage instructions, and avoid assuming that a repair method or spare from another model is suitable.
How we scored these models & further reading
These are our subjective buying scores out of 100. We weigh the usefulness of the features, the intended diving or carrying job, and the compromises involved in owning the gear. They are not laboratory measurements, safety grades or customer averages. The verdict applies to the two named models, not everything either brand makes.
90–100: one of our first choices for the stated job. 80–89: a strong option with trade-offs. 70–79: a more specific fit. A different fit, camera, valve or dive plan can change which one you should buy.
DUI FLX Extreme - DUI Drysuit
- Manufacturer details
- Scuba Diving / ScubaLab: The Best Drysuits for Scuba Diving Reviewed by ScubaLab — 2019
Waterproof D7X Nylotech
Product details and further reading →Questions worth settling
Does the suit material tell me how warm I will be?
No. The whole exposure system, including undergarments, fit, conditions and duration, needs assessment. A shell material or nominal neoprene thickness does not provide a safe temperature limit, and we do not have a controlled thermal test establishing a winner.
Which is the better buy for this particular comparison?
DUI FLX Extreme - DUI Drysuit: The separate FLX HD fabric option should not be confused with this version. Waterproof D7X Nylotech: Fit it over the intended undersuit and include the seal-system spares you want in the complete quote.
Our pick is where we would start. Choose the other model if its fit or features better match your setup—especially where a camera, valve, boot or exposure suit needs an exact match.
