International Standard ISO 3853 `Road vehicles : towing vehicle coupling devices to tow caravans or light trailers : mechanical strength test'.

This International Standard specifies a simplified procedure for testing the mechanical strength of coupling devices fitted to towing vehicles for towing caravans or light trailers of categories O1 (single-axled trailers, other than semi-trailers, with a maximum mass not exceeding 750 kg) and O2 (trailers with a maximum mass not exceeding 3.500 kg, other than trailers of Category O1).