The Alarm Controls 600WP is a weatherproof magnetic lock with a minimum holding force of 600 lbs. The lock is ideal for sliding and swinging gates. Also known as -Alarm Controls Corp. 600LB WEATHERPROOF MAGN LOCK - AC-600WP ALARM CONTROLS 600WP Maglock, 600LB, 12/24VDC, Single, Weatherproof, Aluminum