5/16" Shank size; 2 pieces: 4-7/8" long Cranked Boring Bars; 9 pieces: 3-1/4" long Bit

Made of drop forged tool steel with tungsten carbide tips.

Can be resharpened & reshaped for many times.

Suitable for machining mild steel brass copper and plastics.

For metal lathe, mini lathe, milling other general machining operations such as turning & boring.