Extreme Watersport

SANTI Heated Undersuit Flex 2.0

The SANTI Heated Undersuit Flex 2.0 is a lightweight active heating undersuit designed for divers who want dependable warmth without the bulk of a traditional expedition undersuit. Built using flexible Climashield® Contour insulation with integrated heating technology, it delivers excellent mobility, efficient heat transfer and outstanding comfort beneath modern drysuits.

Designed as part of the complete SANTI Heating System, the Flex 2.0 works with a SANTI Thermovalve or Connector and an external battery to provide active warmth during technical, CCR and cold-water diving throughout Australia. It is an excellent choice for divers seeking a lighter heated alternative for regular diving and travel.

Lightweight Heated Design 110W Active Heating External Battery System
SANTI Heated Undersuit Flex 2.0

Choose Your Size

$1,499.95
Most SANTI Heated Flex 2.0 undersuits are supplied to order directly from SANTI. Please allow approximately 6–10 weeks if your preferred size is not currently available. Contact us for current availability, sizing advice or made-to-measure options.
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Product Highlights

Lightweight Active Heating Without the Bulk

The Heated Flex 2.0 combines efficient active heating with a lightweight Climashield® Contour construction, offering exceptional freedom of movement while maintaining reliable thermal protection. Compared with heavier heated undersuits, its streamlined design reduces bulk beneath the drysuit without compromising comfort during long dives.

Integrated heating elements warm the torso, thighs and arms, while the external battery configuration keeps the power source outside the drysuit for added safety and convenience. Even with the heating switched off, the Flex 2.0 continues to provide dependable passive insulation.

Key Features

Key Features

Lightweight Climashield® Construction

Lightweight 180 g/m² Climashield® Contour insulation improves flexibility and reduces bulk beneath the drysuit.

Integrated Active Heating

110W heating system distributes warmth across the torso, arms and thighs.

External Battery Compatible

Designed for use with SANTI Thermovalve or Connector and an external battery.

Excellent Freedom of Movement

Flexible construction provides unrestricted movement for recreational and technical diving.

Technical Details

Technical Specifications

The Heated Flex 2.0 is SANTI's lightweight heated undersuit, combining Climashield® Contour insulation with integrated active heating technology. It is designed for divers seeking a thinner heated solution that maintains excellent mobility beneath a drysuit while delivering dependable warmth.

Heating Power
Maximum 110W
Heating Temperature
Maximum 45°C
Insulation
Climashield® Contour 180 g/m²
Warmth Rating
0.96 CLO
Battery System
External SANTI Heating System
Heating Zones
Torso, arms and thighs
Weight
Approx. 2.5 kg (Men’s L)
Best Suited For
Technical, CCR, recreational and travel diving
Sizes
Men’s, Women’s & Made-to-Measure
Compatibility
SANTI Thermovalve or Connector only
Included

What's included

  • SANTI Heated Flex 2.0 Undersuit

External battery, Thermovalve and Connector are sold separately unless otherwise stated.

Size Guide

Need Help Choosing Your Size?

Use the size guide below as a reference before ordering. If you are between sizes or plan to wear additional base layers, contact us and we can help recommend the most suitable fit.

Men’s Size Guide

SANTI Heated Undersuit Flex 2.0 men’s size guide

Women’s Size Guide

SANTI Heated Undersuit Flex 2.0 women’s size guide

Why Choose the SANTI Heated Flex 2.0?

The SANTI Heated Flex 2.0 is designed for divers who want the benefits of active heating without the bulk of a heavy expedition undersuit. Combining lightweight Climashield® Contour insulation with an integrated 110W heating system, it delivers dependable warmth while maintaining outstanding flexibility and freedom of movement beneath your drysuit.

Unlike traditional heavyweight thermal systems, the Heated Flex 2.0 is comfortable enough for regular recreational diving while offering the additional warmth required for technical diving, CCR diving and extended cold-water dives.

Built for Melbourne and Australian Cold-Water Diving

Whether you're shore diving around Port Phillip Bay, exploring Victorian wrecks or diving throughout Tasmania and southern Australia, the Heated Flex 2.0 provides dependable active warmth without unnecessary bulk. It is particularly well suited to divers who experience changing water temperatures throughout the year and want a versatile heating system for regular use.

Heated Flex 2.0 vs BZ420X Heated

Both heated undersuits use the SANTI Heating System, but they are designed for different applications. The Heated Flex 2.0 prioritises lightweight comfort, flexibility and travel-friendly performance, making it ideal for everyday recreational and technical diving. The BZ420X Heated provides significantly greater passive insulation and is better suited to expedition, cave, CCR and extreme cold-water diving where maximum warmth is required.

Build Your Complete SANTI Heating System

The Heated Flex 2.0 is designed to work with the SANTI Thermovalve or Connector and an external battery system. Combined with the correct heating accessories, it provides a modular active heating solution that can be adapted to different diving conditions, water temperatures and dive durations.

Why Buy from Extreme Watersport?

Extreme Watersport is an authorised SANTI dealer in Australia, supplying genuine SANTI heated systems with expert advice from experienced cold-water and technical divers. Whether you're comparing the Heated Flex 2.0 with the BZ420X Heated or choosing your first heated undersuit, we'll help you build the right heating system for your diving goals.

FAQ

SANTI Heated Undersuit Flex 2.0 FAQ

Who is the Heated Flex 2.0 designed for?

The Heated Flex 2.0 is ideal for divers who want active heating without the bulk of a heavy expedition undersuit. It suits recreational, technical and CCR divers looking for a lightweight heated solution for regular cold-water diving.

Can I use the Heated Flex 2.0 without turning the heating on?

Yes. The Climashield® insulation continues to provide effective thermal protection even when the heating system is switched off, making it suitable as a standalone drysuit undersuit.

Does the Heated Flex 2.0 include a battery?

No. The undersuit is designed to work with the SANTI Heating System using a compatible Thermovalve or Connector and an external battery, which are sold separately unless included in a package.

What's the difference between the Heated Flex 2.0 and the BZ420X Heated?

The Heated Flex 2.0 focuses on lightweight active heating and excellent freedom of movement, making it ideal for regular diving and travel. The BZ420X Heated offers greater passive insulation and is better suited to extreme cold-water, expedition, cave and long-duration technical diving.

Is the Heated Flex 2.0 suitable for technical and CCR diving?

Yes. The Heated Flex 2.0 is an excellent choice for technical and CCR divers who want active heating while maintaining a lightweight, flexible thermal system beneath their drysuit.

Can I order a made-to-measure Heated Flex 2.0?

Yes. Standard men's and women's sizes are available, with made-to-measure options offered by SANTI for divers requiring a customised fit.

Need Help?

Need Help Choosing the Right Heated Undersuit?

Not sure whether the Heated Flex 2.0 or the BZ420X Heated is the better choice? Our experienced team can help you compare warmth, flexibility, bulk and heating system compatibility to build the ideal SANTI thermal setup for your diving.

Contact Us for Advice