Stainless Countersunk Screws 4 BA x 7/8". £3.68/10. e mail lostignition8@gmail.com for full list of BA screws in Steel, Brass and Stainless. Socket screws in steel and stainless. Taper Pins in Steel and stainless. Model Engineer Taps and dies. BA taps and dies. Washers, nuts in Steel, Brass and Stainless.