1/4″ UNF Hex Dome

A 1/4 BSF hexagon bolt (part threaded)Under head dimension: 2-1/2". Thread length: 9/16". Standard hexagon size (.445" A/F)Head machined flat (no markings).

A 1/4 BSF hexagon set bolt (threaded up to head)Under head dimension: 5/8". Standard hexagon size (.445" A/F)Head machined flat (no markings).

A 5/16 BSF hexagon bolt (part threaded)Thread length 5/8"Under head dimension: 3". Standard hexagon size (.525" A/F)Head machined flat (no markings).