American-made HSS drill bits with an M-2 hardness rating
Black anodized and are standard jobber length
Come in packages of 1 dozen
Used for sheet metal shops
(both of these numbered bits are used heavily in the aircraft industry)
 
 
Product ID:
1570 #21 HSS Jobber Bits - Dz 
1571 #30 HSS Jobber Bits - Dz