scope:

This Standard specifies the characteristics of full-length parallel grooved pins with pilot which have three equally spaced grooves impressed longitudinally on their exterior surface and a pilot to facilitate insertion, with metric dimensions and nominal diameter, d₁, from 1,5 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 positive locking fit when these grooved pins are forced into a drilled hole equal to the nominal diameter d₁.