21 X 12″ Aircraft Extension Drill Bit Cobalt GLBCOX1221 New Release

Specs

Quantity: 1 piece

Size: #21

Overall length: 12 in

Material: Cobalt alloy

Type: Extension drill bit designed for deep-hole applications

Features

Cobalt alloy provides enhanced wear and heat resistance for drilling through tougher metals compared with standard HSS bits

12″ extension length enables access to deep holes in confined spaces such as engine bays, chassis, and aerospace components

Rigid extension design helps maintain straightness and consistent hole geometry during deep-hole drilling

Ideal for metal fabrication, maintenance, and repair tasks where depth and material hardness are factors

Single-piece delivery simplifies inventory and ensures a ready-to-use long-reach bit when needed

Physical

Length: 12 inches

Diameter designation: #21

Construction: Cobalt aircraft extension bit (long-reach drill bit for hard metals)