Ball-peen hammer

In the word "ball-peen", peen, sometimes written pein,[2][3][4] probably comes from a North Germanic source; compare dialectal Norwegian penn (“peen”), Danish pind (“peg”), German Pinne (“the peen of a hammer”), Old Swedish pæna (“to pound iron with a hammer”).

[5] Besides peening (surface-hardening by impact), the ball-peen hammer is useful for many tasks, such as striking punches and chisels (usually performed with the flat face of the hammer).

[6] Variants include the straight-peen, diagonal-peen, and cross-peen hammer.

The cross-peen hammer's wedge is oriented perpendicular to the handle.

Ball-peen hammer heads are typically made of heat treated forged high-carbon steel[8] or alloy steel; it is harder than the face of a claw hammer.