Retractable nail device

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.