The Mares Undersuit 2mm Open Cell is an open-cell neoprene open cell built specifically for freedivers and spearfishers. The 2mm open-cell inner surface moulds to the body like a second skin, trapping a micro-layer of warm water that insulates effectively even during long, static breath-hold dives. Supple and unrestricted, it’s the kind of gear that disappears on your body at Mabul’s sandy hunting zones.
Technical Specifications
| Specification | Details |
| Brand | Mares |
| Model | Undersuit 2mm Open Cell |
| Thickness | 2mm |
| Gender | Unisex |
| Material | Open-cell neoprene (inner) |
| Zipper | Side zip / no zip |
| Stitching | Glued seams |
| Seams | Open-cell sealed |
| Best For | Freediving, Spearfishing, Apnea diving |
Key Features
- Open-cell inner surface: Moulds to the body like a second skin for maximum insulation during static apnea dives.
- Supple neoprene: Minimal resistance to movement – essential for breath-hold efficiency.
- Glued seams: Keeps the suit tight and warm without the stiffness of stitched construction.
- Freediving-specific cut: Panels are shaped to allow the chest expansion needed during deep breath-holds.
Suited for Malaysian Dive Sites
The Mares Undersuit 2mm Open Cell performs reliably across Malaysia’s premier diving destinations. Whether you’re exploring Mabul’s sandy hunting zones, or venturing to new reefs and wrecks, this wetsuit delivers the warmth, flexibility, and comfort you need on every descent.
Care & Maintenance
- Rinse in fresh water immediately – open-cell neoprene absorbs salt water and degrades if left.
- Never tumble dry; hang flat or lay on a towel to dry slowly.
- Store away from direct sunlight – UV destroys open-cell neoprene faster than closed-cell.
- Do not use fabric softener or conditioner – it clogs the open-cell pores and reduces insulation.
Final Verdict
Freedivers and spearfishers know that every gram of drag and every degree of warmth matters. The Mares Undersuit 2mm Open Cell delivers on both – a suit that gets out of your way and keeps you comfortable on the breath-hold.




Elizabeth Wong –
This undersuit is truly a game-changer. I was worried about the fit, but it’s perfect. The 2mm thickness is just right for our diving trips. I’ve used it in several dives already and it’s still looking brand new.
Ivy Low –
How does it provide the perfect blend of flexibility and protection for the wearer in colder water conditions?
Junhao Lo –
Thank you for reaching out to us, Ivy. The Mares Undersuit 2mm Open Cell is designed to provide excellent flexibility and protection for the wearer in colder water conditions. The 2mm thickness offers a good balance between flexibility and thermal insulation, allowing for ease of movement while keeping the wearer warm. This is achieved through a combination of the suit’s material and construction, which is designed to retain body heat and protect against cold water. We’re glad you’re interested in learning more about this product!
Khairul Anwar –
Took this for my first-ever scuba diving. The material is a bit stiff, but it’s fine once you’re in the water. It’s also easy to put on and take off. Overall, I’m satisfied with this purchase!
Lee Chen –
I’m not sure if it’s really worth the money. The overall performance is decent, but I’m not blown away.
Gabriel Sia –
What makes this undersuit more suitable than a traditional onesie for diving?
Imran Hanafiah –
Thanks for your question, Gabriel. The Mares Undersuit 2mm Open Cell is designed to be more suitable for diving than a traditional onesie due to its unique open-cell construction. This design provides a snug fit while allowing for flexibility and movement, reducing drag and improving overall comfort during dives. Additionally, the open-cell construction helps to conserve body heat, keeping you warmer in cold water conditions. The undersuit also features a quick-release zip and adjustable leg cuffs for a secure fit.
Fionn Wong –
This undersuit has exceeded my expectations! The buoyancy is great, and the material is so soft and comfortable.
Elaine Kang –
I’ve been using the Mares Undersuit 2mm Open Cell for a month now, and I’m thoroughly impressed with its quality and performance.
Leong Wei Zhong –
Can I use it in cold water without freezing?
Imran Hanafiah –
Thank you for your review, Leong Wei Zhong. The Mares Undersuit 2mm Open Cell is designed to provide thermal protection in cold water, but its suitability depends on individual preferences. Generally, this undersuit is designed to be warm in water temperatures around 12-18°C (54-64°F). We would advise exercising caution if using it in very cold water, as personal tolerance to cold may vary significantly. If you have any further questions or concerns, please feel free to ask.
Amena Chandran –
I recently purchased the Mares Undersuit 2mm Open Cell and I must say it’s been a game-changer for my diving expeditions.
Tanisha Thananjayanananda –
One minor issue I’ve encountered is that it sometimes takes a while to dry.
Farhan Salleh –
How does it prevent water ingress through the zipper?
Junhao Lo –
Thank you for your question, Farhan Salleh. The Mares Undersuit 2mm Open Cell features a sealed zipper to prevent water ingress. The zipper is designed with a specialized seal that helps to keep water out, ensuring that you stay warm and dry during your dive. If you have any further questions or concerns, please don’t hesitate to ask.
Tara Lim –
I recently purchased the Mares Undersuit 2mm Open Cell to scuba dive in cooler waters, and it’s been a lifesaver.
Hassaniah Rasmon –
Will it work well with a wetsuit during the monsoon season?
Imran Hanafiah –
Thank you for reaching out to us about the usage of the Mares Undersuit 2mm Open Cell during the monsoon season. While it’s designed to work as an undersuit under a wetsuit, the performance may vary depending on the conditions. The 2mm thickness might provide some protection, but the open-cell structure can be prone to water absorption, which might affect its insulating properties in wet conditions. We recommend testing the undersuit in similar conditions before using it during the monsoon season. If you have any further questions, please don’t hesitate to ask!