Unimat lathe boring bar holder was machined from 6061-T6 aluminum and designed to hold 0.5” diameter boring bars. The T6 temper is a very strong and a good choice for tooling for the 3” swing lathe. This particular size holder allows using more tooling from my other lathes. The various clamping screws are 8-32 stainless steel socket head screws. Also the center clamping screw allows aligning boring bars made with flats for setting their alignment.