Their initial foray was in the early noughties when the British manufacturer launched the Xerotherm. This popular two piece base layer has stood the test of time, perhaps because it is made from a lightweight, yet warm material that was originally developed for NASA. (At the time it was the lightest, warmest fabric going). Now the British manufacturer has evolved the HALO. They unveiled the A°R at the 2019 DEMA Show in Orlando with the promise that this high performance low bulk garment is their warmest undersuit to date. Although it might not seem like it, the HALO A°R has taken a long time to come to market, because it combines baffle technology with an extreme insulation product (nicknamed 'A°RGON' by FE) which is favoured by the cryogenics and space exploration sectors.

Me Too Products

Fourth Element have chosen to name the extreme insulation material 'A°RGON' and I can understand why. Over the years I have observed at dive shows across the planet subtle, blatant, and sometimes down right shoddy copies of successful pieces of equipment developed by the likes of Fourth Element, Waterproof and Custom Divers. It therefore makes sense that when a company has invested significant time and funds in research and development, that they do not give away propriety information.

The HALO A°R

I have been reporting on Fourth Element products since they launched back in 1999, hence I am aware that they started experimenting with the 'A°RGON material about 13 years ago. "Since then we have done a lot of research and experimenting. We knew what we were looking for, and eventually we found the right stuff. About 18 months ago, we got the final iteration correct", stated Jim Standing. The suit has been designed to ensure that heat loss from the torso is minimised when the diver is in horizontal trim, hence the suit has been augmented with A°RGON material from the shoulders to the knees.

Environmental Testing

Fourth Element put the HALO A°R through a number of test in various environments, including a 'cold room' where the temperature can be controlled and capable of -17C. conducted a series of tests in an environmentally controlled 'cold room'. This room was capable ot going to 17=c. Fourth Element have looked to the stars and the cryogenics industry to source "the right stuff" Now the British manufacturer has evolved the HALO and launched the A°R undersuit at the 2019 DEMA Show.

Key Features

• A°RGON™ - extreme performance thermal insulation
• Bodymapped thermal protection
• High performance / low bulk
• Optimised for horizontal trim
• P-valve ready - both male and female suits
• Exceptional warmth
• Waterproof outer layer
• All-way stretch fabric for snug fit
• Perfect over J2 baselayer
• Machine washable - up to 30°C / 86°F
• 16 UK Female Sizes - 6, 6 short, 8, 8 short, 10, 10 short, 12, 12 short, 14, 14 short, 16, 16 short, 18, 18 short, 20, 20 short
• 16 UK Male Sizes - XS, Small, Small short, Medium, Medium short, Medium tall, Large, Large short, Large tall, XL, XL short, XL tall, XXL, XXL short, XXL tall, XXXL, XXXL short
• Thumb loops and foot stirrups