Using a fully waterproof, breathable inner liner to prevent the ingress from water, then seal the top using a tapered neoprene collar.Tested to surpass waterproofness of 20,000 mm ….so what does this mean? Well basically the liner has been tested to withstand heavy rain, and wet snow under high pressure!!Also has a rating of 20,000 breathability….so once again what does this mean? As well as not allowing water in, this clever inner material allows sweat, and moisture from your body out, to help keep you cool!The flat inside gives great feel of the frame, and the Jonny Walker developed Enduro sole gives help when pushing the bike, and great gear lever and rear brake control.You must check out the SlideLock Velcro function it really is groundbreaking in security fastening boot technology.Waterproof & BreathableHydraDriEVO Inner Membrane:20.000mm Waterproof20.000g/m² BreathableNeoprene waterproof sealing collarOutstanding comfort with first-class fit even for wide feetSlideLock system, Auto-locking one way sliding closure for great seal at top of bootPolymer composite buckles with Over-lock system and stainless steel baseLow-profile, for easy gear shiftingHeel grip ankle design for stability when riding on your toesEnduro pattern for grip when pushing your bikeDualZone hardnessExtended foot peg riding zone for arch and on the toes riding styleSteel shank reinforced and CE certifiedBreathable mesh 3D liner with anti-slip reinforcement for zero heel lift