INSTANT LIFETIME guarantee WITH THIS PRODUCT! Our award winning socks now with an elasticated cuff providing a water barrier, significantly reducing the chance of water ingress & ensuring the socks stay put however strenuous the activity. Silicon free elastication providing a barrier to water ingress through the top is massively reduced Totally waterproof, breathable & windproof Merino wool lining for moisture control & comfort Hydrostop Usage Guide Seal Skinz Hydrostop technology creates a seal between the sock cuff & skin, helping to reduce the amount of water from running down the leg & into the sock. Due to this close bond between sock cuff & skin, we recommend that Hydrostop socks are only used outdoors & not for a prolonged period of time. Incorrect or prolonged use can result in excessive rubbing against the skin & may in a very small minority of cases cause minor skin irritation. The Hydrostop seal material has been fully tested to EN ISO 10993-5: 2009 & is OEKOTEX compliant.