This International Standard specifies the characteristics of half-length taper grooved pins made of steel or austenitic stainless steel which have three equally spaced grooves impressed longitudinally on their exterior surface, with nominal diameter, d₁, from 1,5 mm to 25 mm inclusive.

The displaced material to each side of the grooves forming an expanded diameter, d₂, which is larger than the nominal diameter d₁ will cause a non-positive locking fit when these grooved pins are forced into a drilled hole equal to the nominal diameter d₁, (see clause 4).