ITEM NAME:5x Black Oxide Finish T-Slot Nuts M8/M10 Threads for T-slots In Machine VMB Descriptio n Description:.Tapped through for 3/8"-16 threads for use with d-rings, racks, tie downs, custom cleats and more. Made from high quality iron steel, these nuts have high hardness and a long service life. We'd like to settle any problem in a friendly manner.