Our txr snow chains are ideal to keep at home or in the boot in case of an emergency they are supplied in pairs and one pair is required per set of driving wheels the chains are diamond shape for maximum traction and are kept in a handy storage box the 16mm snow chains are designed for heavier vehicles or larger tyres up to 20 diameterr snow chains and snow socks should only be used in emergency situations where a vehicle has no traction on thick snow or ice once the vehicle reaches tarma