Snap lock plastic skirting and siding to finishing trim. Makes tabs in the cut edge of siding panel used as a finishing course at top of wall or below window. Tabs lock into utility trim. Punch raises a high projection to compensate for natural relaxation of vinyl plastic. It also works well on aluminum siding but is not recommended for steel. NOTE: The SL5 should not be used when PERMATABS are required to snap into finished trim. For this application we recommend using the Malco SL1 or SL2 Snap Lock Punch. PERMATABS is a trademark of C & H Enterprises. Not Recommended for use below 32 degree F (0 degree C).