DS EN 3305:1997 Aerospace Series - Screws, 100 Degree Countersunk Reduced Head, Offset Cruciform Recess, Close Tolerance Normal Shank, Short Thread, In Alloy Steel, Cadmium Plated - Classification: 1100 Mpa (At Ambient Temperature)/235 Degree C Defines the characteristics of screws, 100 degree countersunk reduced head, offset cruciform recess, close tolerance normal shank, short thread, in alloy steel, cadmium plated.