The DF-1465 bit is our 6.5mm or approximately 1/4-inch High Speed Steel Cobalt (HSCO) spot weld bit. The twist is smaller than the shank which is 8.0mm and has a flat spot on it to be tightened into our DF-15DX Spot Weld Drills (sold separately). This German made bit may be used with off brand spot weld drills. Our drill bits are specifically designed for the abuse of spot weld drilling. Flat ground for strength, centering nib to prevent walking. Our German made spot weld bits are available in 3 sizes, 6.5, 8.0 and 10.0 mm. These Cobalt high-speed steel mix bits are 45mm long and work with all brands of spot-weld drills.