We continually compare and test our Stealth’s welded seams against the comparable stitched alternatives using recognised scientific testing methods.

We use Intertek, a renowned, independent third-party quality assurance provider, to do the testing for us. They test comparable sewn and welded panels to determine which retains heat the best.

We created two identical down-filled pillows in a recent thermal resistance test under BS EN31092-1993 guidelines. The only difference was the seam construction, one pad used Stealth’s welded seams whilst the other was constructed using a comparable stitched alternative.

Both samples used the same 100% Nylon woven fabric, weighing 62gm/sqm, and filled with the same 90% Grey Goose down fill using a baffle box construction.

The results were terrific!

Stitched product warmth returned an insulation rating of: 1.2 CLO*

Stealth welded seams returned an insulation rating of: 3.3 CLO*

With no puncture holes caused by the needle in stitching, Stealth’s welded seam panel was over 90% more insulating than the stitched alternative. In the real world of performance gear, this means that for comparable levels of warmth, a Stealth style may be made of less filler, meaning it’s lighter for the same level of insulation.

*What’s CLO?

CLO is a value that describes the degree of insulation provided by an article of clothing. A CLO value of 1 equals the amount of clothing required by a resting human to maintain thermal comfort at a room temperature of 21 degrees Celsius, or 71 degrees Fahrenheit.