This is a Lixie#O Pin-Head Bronze Mallet.

Pin-Head Bronze Hammers, with a machinist face on one end of the head and a needle nose on the other, are invaluable for the small, fussy tapping and adjusting work involved in precision and bench work. The head design allows excellent accessibility to limited working areas.

Specifics:

Part Number: O

Head Length: 3"

Overall Length: 11"

Weight: 7 oz