Alvord Polk 03083 Solid Pilot Counterbore: 0.4134" Dia, 0.2559" Pilot
Solid Pilot Counterbore: 0.4134" Dia, 0.2559" Pilot 0.2362" Socket-Head Cap Screw Compatible, 5/16" Shank Dia, 5-5/8" OAL, High Speed Steel
$52.28