The Rooster® ThermaFlex™ 1.5mm Longjohn; Unsurpassed versatility. Pair with a 1.5mm ThermaFlex™ top in warmer climates; add PolyPro™ underneath for a warmth boost or wear as a winter layer when it gets cold. Perfect with or without the ProHike Pads, this Longjohn should be in your gear bag! When used with Rooster® ProHike Pads enjoy the ultimate in hiking support or when worn alone make use of the unrestrictive fit and superior shock protection.