The oxford boss alarm 16 mm & chain lock 12 mm x 1.5 M black lk481 is part of the latest oxford collection. This chain lock features oxford's strongest ever lock with an integral alarm. The padlock has a 16 mm shackle and an ear-splittingly loud 100 db alarm which is triggered by movement sensors the padlock can also be engaged without setting the alarm . Combined with a 12 mm hardened steel chain, the boss alarm chain lock will put off any would-be bike thief. The oxford boss alarm chain lock has been independently tested and approved by sold secure and has been awarded powered cycle motorcycle gold standard, sbsc and art 4*. Insurance discounts are available in the uk when you use this lock. This lock has a key replacement service. When you buy your lock, simply note down the number which comes either attached to the keys on a metal tag or is laser marked on each key. Key features points: sold secure gold, sbsc & art 4* certified 12 mm chain links tough double locking padlock weatherproof 100 db alarm module padlock doubles as a disc lock view all oxford security chains & locks. View all security chains, cables & u-locks.