Thermal Fusion Undergarment

$479Free shipping on all orders!

It's not just our best-performing scuba undergarment, it's the best. In independent laboratory tests conducted by the Sport Innovation Center (SPIN), the Thermal Fusion came out on top for protecting skin and core temperatures. Made of two layers of specialty materials for warmth, stretch, and overall comfort.


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Trusted since 1943

ABOUT Thermal Fusion Undergarment

Product Details


  • Thermal Core Technology Patented dual layer design provides a streamlined fit with an unlimited range of motion
  • Polartec®️ Power Stretch®️ Pro™ Fleece The outer layer utilizes a high stretch, high-loft fleece to conform to the shape of your body. This fleece is well known for its durability in laundering.
  • Polartec®️ Classic Fleece The inner layer is a breathable, high-loft fleece that wicks moisture and delivers superior warmth
  • SPIN Rated The Thermal Fusion was rated higher than competitor undergarments for warmth in cold water immersion and cold weather environmental tests
  • Stirrups and Loops Foot stirrups keep the garment from riding up. Thumb loops keep sleeves in place and allow air transfer when using dry gloves.
  • YKK Relief Zipper A two-way zipper provides added convenience
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Size Guide - Scuba Diving Drysuits

Size Chart - Aqua Lung Scuba Diving Drysuits

Sizes shown here are estimations. For best sizing, it is recommended to try on your drysuit at an authorized dealer.