This European Standard provides specifications for safety@ quality and performance requirements for supplementary grip devices@ commonly called ??SGDs??@ for type ?C approved tyres according to the current legislation@ intended to be fitted on tyres on vehicles in categories M1@ N1@ O1@ O2 and relevant sub-categories (off road vehicles). The requirements contained in prEN 16662-1 apply to all SGDs@ regardless of the material/technology used to build it. In case there are available standards for the specific technology of the device@ they are intended to be used in conjunction with prEN 16662-1. In case no standard is available for the specific technology@ prEN 16662-1 applies. All tests included within this standard are intended to be performed with activated ABS. NOTE The choice of performing additional tests with ABS disengaged is left to each manufacturer to decide individually.