Abstract: A device for locking sheet metal standing seam roof panels of the type where a male leg portion of the seam is lifted up into a female leg portion of the seam in order that a partially punched and extending outward locking button on the male leg engages a turned-up hook on the female leg portion, the device comprising a pair of elongated means attached to the jaws of a duck bill toggle type pliers for urging the male leg portion into the female leg portion for locking, one of the pair of elongated means comprising a right angle iron piece adapted to encompass the apex of the rolled over female leg portion which forms the cavity, and the other of the pair of means a square rod adapted to engage a downward extending lip on the male leg portion forming the protrusion, each of said elements attached to different jaws of the duck bills of the vise grips, such that the toggle type pliers being placed into position and closed results in the square rod engaging downward extending lip and pushing upward into position