Tested in accordance to Japanese Industrial Standards – JIS S 1037:1989 JIS S 1037:1989 & achieved an integrity of 82 Minutes over 1 hours @ 1000°C. APS Strike bolt are made from solid 2′ diameter Polish Shaft finished with chrome. APS 7 Lever double bit Key Lock. Length & teeth design were designed to deter lock picking & has a safety locking/unlocking feature used in most banks. APS Best selling model for Commercial Series has a wall thickness of 86mm each side Secured by a thick fire & burglary barrier. Able to withstand up toll 1000°C of continuous burning. APS Vertical rebate is situated right behind the door acting as a safety latch to prevent door opening from cutting of hinges. Be sure your door will stay where it is even without its hinges.