Power staple gun

A power staple gun comprising:

• a gun body;
• a staple nozzle downwardly extended from said gun body at one end;
• a coupling frame downwardly extended from said gun body at an opposite end and substantially disposed in parallel to said staple nozzle;
• a magazine connected between said staple nozzle and said coupling frame to hold staples, said magazine comprising two rectangular guide boards longitudinally disposed at two opposite sides, at least two pairs of parallel staple grooves within said guide boards for receiving staples of different lengths, and a staple loading port on one guide board, said staple loading port comprising a straight top side, a straight bottom side being an elongated through hole, a straight lateral side disposed closer to said coupling frame and connected between said straight top side and said straight bottom side, and a stepped lateral side disposed closer to said staple nozzle and connected between said straight top side and said straight bottom side opposite to said straight lateral side, said stepped lateral side comprising a series of steps and a plurality of marks at one side by each step to show different lengths corresponding to said staple grooves, each step comprised of a horizontal portion and a vertical portion connected at right angles, the horizontal portions of said stepped lateral side being respectively aligned with said staple grooves;
• and
• a follower member disposed in said magazine at one end for pushing staples toward said staple nozzle.