Reaper Cobalt Drill Bits are constructed of a patented 8% cobalt and high-molybdenum alloy, which increases the drill bit strength, and allows for greater heat resistance when drilling the hardest and most demanding materials. Reaper Cobalt Drill bits feature a 135-degree split point, eliminating pilot hole predrilling or starter punching. Shanks on sizes 3/16” and greater have 3, machine-ground flats, which prevent slippage in drill chucks.