Trine EN Series electric strikes are UL listed, 10C Fire-Rated and 1034 Indoor Outdoor Burglary Resistant. The EN Series has only one locking mechanism. We have tested this product well and beyond BHMA GRADE 1. Durability-1,000,000 life cycles and Holding Force-2000 lbs. UL tested. The UL outdoor rating and EN400 Gatebox allows the strike to go where others never could.