THE KRYPTONITE NEW YORK CHAIN/DISC LOCK

This is one of Kryptonite's toughest locks!  The chain is made from 10mm four-sided trapezoidal chain links constructed from triple heat-treated boron manganese steel.  The inner width of the chain links is slightly narrower to defend against leverage attacks.  This chain is secured with a 13mm hardened Kryptonium steel shackle with a highly secure disc-style cylindrical lock.  It comes with three keys, one lighted for use in dark places.  This lock is recommended for high crime areas.