This document is to be used on cutting edges and end bits in conjunction with metric bolts typically used on off-road, self-propelled work machines as described in SAE J1116. This document specifies the principle shapes and dimensions for countersunk square holes.
SAE J1580-1989 history
2011SAE J1580-2011 Metric Countersunk Holes for Cutting Edges and End Bits
1989SAE J1580-1989 Metric Countersunk Holes for Cutting Edges and End Bits