Check the listing for details. 6-48 tpi High Carbon Steel 4 PIECE Tap + #31 Cobalt + Starter Drill Super Set. Condition: New. Listed at 29.99 USD. New Page 1 516 6-48 tpi High Carbon Steel Tap & Drill Super Set Hard to Find Commonly used to tap and drill receivers for scope mounts Set includes: 1each 6-48 tpi Plug Tap 1each 6-48tpi Bottom Tap 1each #31 Cobalt High Speed Drill 1each #3 Double Point Starter Drill Bit Use the Starter Bit to get precision hole placement on Hard Receivers. No more dancing drill bits on Hard Receivers Once the hole is started you still need to finish drilling with the #31 bit High Carbon Steel taps. If one should break off in a hole, the remains can be “shattered” with a punch for easy removal. Not so for HSS taps, break an HSS and your SOL See My other auction for other sizes of Tap and Drill Sets Check out my other ItemsNew Page 1 516 6-48 tpi High Carbon Steel Tap & Drill Super Set Hard to Find Commonly used to tap and drill receivers for scope mounts Set includes: 1each 6-48 tpi Plug Tap 1each 6-48tpi Bottom Tap 1each #31 Cobalt High Speed Drill 1each #3 Double Point Starter Drill Bit Use the Starter Bit to get precision hole placement on Hard Receivers. No more dancing drill bits on Hard Receivers Once the hole is started you still need to finish drilling with the #31 bit High Carbon Steel taps. If one should break off in a hole, the remains can be “shattered” with a punch for easy removal. Not so for HSS taps, break an HSS and your SOL See My other auction for other sizes of Tap and Drill Sets Check out my other Items