Designed and manufactured to BS 1210 Standards - major diameter and threads excepted. 25ø sharp point and single leading thread for a fast start and improved thread acceptance. 60ø Twin-threads with parallel shank for faster insertion and greater pull out resistance. Large core diameter for extra strength. Surface hardened up to 750 HV to prevent torque shearing under load and a core hardness of up to 450 HV for improved ductility. Plated in zinc to a minimum of 7.5 microns and black passivated. Made from C10-18 Steel to ensure consistent quality. Double countersunk reduces the likelihood of head shear and assists completion of countersinking. Full batch-traceability to the original steel mill certificate. Suitable for TIMco and all other leading plastic expansion plugs. For general applications into softwoods and various types of hardwood.