This International Standard specifies a crevice forming technique and crevice former which are intended to be used for crevice corrosion testing of flat specimens or tubes of stainless steels, in corrosive solutions. This International Standard specifies no information concerning how the crevice corrosion testing shall be performed and how the attack shall be evaluated. The crevice former specified in this International Standard can be used for electrochemical measurements, if the specimens are designed for electrical connections.