Hex Screw - 3-inch (M8 x 70)

Cavalry hex screws in M8, seventy millimetres long, supplied by the box. The extra length over the 50mm is about what the bolt has to pass through before the nut goes on: two thicknesses of steel plus a bracket, a frame with packing behind it, timber bolted to steel, or an assembly with a spacer or a bush between the parts. Too short and the nut runs out of thread; too long and it stands proud where it will catch. Turned with a spanner or socket so it pulls up tight and comes apart again cleanly. Boxed because at this length the fixings are usually structural and needed in quantity - machine frames, gate posts, racking, mezzanines and steel-to-timber connections.