DIN 787 Bolt: T-slot · Products: 38 DIN 787 - Bolts for T-slots One-piece T-slot bolt: a forged head with two flats and a neck with milled flats carry the thread, so it replaces a DIN 508 T-slot nut with a DIN 6379 stud. It fastens workpieces and fixtures in DIN 650 T-slots on machine tool tables, workholding plates and fixtures.