Capstan screws are precision fasteners with a flat cylindrical head that contains multiple radial holes. These holes allow insertion of a bar or rod for tightening and adjustment, providing controlled torque in applications where standard screwdrivers or wrenches cannot be used. A4 / 316 Stainless Steel fasteners are "marine grade" corrosion resistant; suitable for outdoor and salt water environments. A4 fasteners also offer increased resistance to chemicals when compared with A2 stainless fasteners.
