5/16"x6" Cobalt Aircraft Extension Drill 2141220 Proform Air Breather Caps for

Proform Air Breather Caps for Chevrolet 141-754

Mack EO-M Plus

2 1978-1979 (Rear)

Valve rocker cover

Eliminates grinding wheel heat build-up and extends wheel life

5/16"x6" Cobalt Aircraft Extension Drill 2141220 Proform Air Breather Caps forNational Aerospace Standard 907, Type J Cobalt Drills, 6" OAL with Jobber Drill Flute Length, Cobalt Extension Drill, Cobalt HSS, Surface Treated, 135 Split Point These cobalt jobbers length drills are used for drilling in tough, high tensile strength materials like stainless steels, titanium and inconel. They are made of cobalt high speed steel, with heavy duty flute construction and 135 split point.