It is highly reccommended that you add a layer of underwear to all suits (especially any single-layer suit) for any additional protection. The extra layer of flame retardant material is an item that no driver should ever have to use, but, if you need it, you will be glad you have it. The soft knit is hypoallergenic and more comfortable on the skin that the old standby. The double stitching provides added durability.

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