Nascom's N505ASCD is a short, 2" block switch with an L bracket, designed for rollup or curtain doors. It combines the installers' choice of contact configuration with an N35 NdFeB magnet for maximum gap performance.gThe N505ASCD prevents false alarms caused by warping or shifting of doors, and features our unique NO DEAD SPOT? technology.FEATURESNO DEAD SPOT? TECHNOLOGYEXTRA WIDE GAP - N35 NdFeB RARE EARTH MAGNETPROTECTIVE WEAR PADLISTED TO UL634 STANDARD24" ARMORED CABLE LEAD PROTECTION36" 22AWG WIRE LEADSEXTRUDED ANODIZED (TYPE II) ALUMINUM