When the door is closed, the shear lock locking pins will slide into the cavity of the 'shear lock keep' to produce the locking action, and giving a high physical shear holding force, this design of holding force is much different from an electromagnetic lock, however, due to the initial 'Pull in' current draw of the unit, it is recommended that you use a 2amp 12v dc or 1amp 24v dc power supply
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