Von Duprin 6211 FSE 24VDC US32D Heavy-Duty Electric Strike for Cylindrical Lock, 24VDC, Stainless Steel Finish For use with mortise/cylindrical locks on single door applications; designed to replace Von Duprin 3140 or Folger Adam 712 Fail-secure - requires power to be applied to unlock the strike lip; on loss of power, the strike lip is locked; Fire-rated Strike box is adjustable to compensate for misalignment of the door or frame Two piece plug connectors are furnished for ease of installation and for removal during strike servicing Static strength 1300 lbs; Dynamic strength 70 ft-lbs; Endurance 1,000,000 cycles