Patent ID: 7744323

Claim:
A retractable nail for attaching a solid, fibrous or cellular material, which can be retracted without seriously destroying or damaging said material, said nail comprising: a head portion comprising an elongated shape main head, the main head comprises a striking face and a slot configured for receiving a removal tool; a secondary head attached to the main head, the secondary head breaks away from said main head when said removal tool is actuated; a piercing part; and a longitudinal main body comprising a front and rear sides with a helical thread along its longitudinal surface and two lateral sides substantially planar without said helical thread; wherein a first width between said lateral sides is preferably larger than a second width between said front and rear sides; and wherein gaps between said helical threads are substantially filled with a protective material to prevent damage to said helical threads when said nail is hammered or bored pneumatically or electrically powered into said solid, fibrous or cellular material.