Type SB: Non-mushrooming / Safety Type Hammer
Metocraft bronze hammers are made of a special bronze alloy and specially designed cored opening in the head, so that repeated blows will deform the metal inwardly rather than mushroom the head. Danger of flying pieces from a mushroomed head is thereby eliminated. 

These heads are non-sparking and they are well secured to a straight-grained hickory handle by means of a spring type cross pin that may be easily removed for handle replacement, if necessary.

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