Six sided 12mm chain made of 3t hardened manganese steel Includes Evolution series 4 Disc Lock with 14mm MAX-Performance steel shackle Hardened double deadbolt locking for extensive holding power High security disc-style cylinder with reinforced anti-drill, anti-pull protection system 3 keys (1 w/light) 12mm 3`3`/99cm Key Blk 9 of 10UPC/EAN/GTIN: 720018999515