Patent ID: 7481143

Claim:
An alignment device comprising: a body including: an alignment edge configured to guide a cutting device; an extension portion pivotal relative to the alignment edge, biased to an alignment position where the extension portion extends outward from the body and is perpendicular to the alignment edge when in the alignment position and where the extension portion is configured to swing to a pass-through position upon contact with the cutting device and automatically return to the alignment position upon passing of the cutting device; and at least one cutting-line indicator configured to be selectively positioned on the extension portion and configured to indicate a cutting line for the cutting device during cutting operation, a retention edge configured to abut a plank, where the retention edge extends parallel to the plank and where the retention edge is fixed perpendicular to the alignment edge forming a right angle with the alignment edge; and; a hypotenuse edge opposite the right angle to form a right triangle for use as a carpenter's square.