Material: Made of high speed steel, high hardness and wear resistance. The center spindle of the drill bit is spring loaded. Suitable for: Double-sided sharp blades for high efficiency. Suitable for thin stainless steel sheet, iron sheet, aluminum sheet, F.R.P or other thin sheet EASILY SEPARATE: Spot welding cutting bit to easily separate spot welded panels without deforming the sheet. Separate the spot welded sheet, panel, etc. and cut the small access holes Double Sided: This weld cutter is a double sided rotary cutting blade that separates spot welded panels more efficiently than a panel cutter. 3/8 inch Double Sided Rotary Blade and Hex Shank for Most Drill Bits Spot Welding Cutting Tool: Easy to replace blades when they start to dull Product description Color: 13pcs The package includes 1 x drill with cutter 2 x pilot pin 10 x Extra 3/8 " knives. Product features: Type: Double-sided Rotary Spot Welding Cutter Material: HSS The diameter of the part of the saw tooth: 3/8 " (9.5 millimeters) Net weight: 2.2 oz (62 g) Usage: iron cast iron alloy steel carbon steel die steel