Kryptonite New York Chain 1217 and Evolution Disc Lock: 5.5' (170cm)Kryptonite New York Chain 1217 and Evolution Disc Lock: 5. 5' (170cm) This high security lock features an innovative oval crossbar disc lock, designed to defeat maximum attacks. 12mm six sided chain links made out of 3t manganese steel 14mm hardened MAX Performance steel shackle Hardened double deadbolt design provides protection against twist attacks Includes three stainless steel keys: two standard "I" keys and one LED lighted key Security Rating: 9