Hex Cap Screws- also known as machine bolts or hex bolts are available in various bolt grade markings and strengths. This bolt has a hex head and smooth shoulder – the threaded portion is twice the diameter plus one quarter of an inch for bolts six inches in length and shorter – for those over six inches in length it plus one half of an inch. Please see the FSP Fastener Identification Marking Chart on this website for head markings.


Tap Bolts– these are fully threaded hex head bolts.