DIN6325 Metric Hardened & Ground Dowels are produced to a precise Interference fit. Our standard metric size range is from 1mm up to 25mm diameter and is produced from material 1.3505 (100cr6) Through Hardened to HRC58-62. This pin is configured to have a radius at one end and a ‘crown’ at the other – a crown can be more easily described as a radius on top of a chamfer.