This is a bulk pack of 25 chuck keys holders model 48-66-4040 for tightening chucks 48-66-0240, 48-66-0795, 48-66-0797, 48-66-0805, 48-66-1360, 48-66-5185, 48-66-1381or 48-66-2100 on it.
For use with chuck keys 48-66-3080, 48-66-3240, 48-66-3280 and 48-66-3480.