Construction in accordance with DIN 838,ISO 3318,ISO 1085,ISO 10104,GEDORE vanadium steel 31CrV3,chrome-plated,* not standardised,Non-mirroring,matted surface,Carefully forged and expertly machined: Ring: thin-walled,deeply swaged and angled at 5°,with UD profile - for gentle force transfer,High bending rigidity - does not break or splinter under overload, minimising the risk of injury,Overloading is indicated by deformation,For extremely deep or countersunk bolts or nuts,High-quality industrial grade for continuous loading under harsh conditions