Size and Fitness: Generally speaking, S for 1-2.5kg / M for 2.5-4.5kg / L for 4.5-7kg Effect: Prevent pets from sliding on wood floors, protect sofas from pet scratches, help weak pet get up easier. Feature: Anti-slip silicone gel on the soles to provide extra traction, rubber reinforcement inside the socks to be easy to hold. Package and measure: Set of 4 socks, select the correct size according to your dog’s paw width, measure it referring to picture 2 before buying.