Sure to shock any thief and aiming to send them running, Abus equipped this lock with an alarm that blasts out at over 100dB (as loud as a circular saw or live rock band playing on stage). This alarm system uses an industry proven 3D Position Detection system that registers even the slightest movements. Should a thief tamper with your bike, the alarm sound immediately to notify everyone in the surrounding area. Constructed from Specially Hardened Steel This ultra-securing lock features a 12mm round shackle and the shackle itself, the main lock body and the load-bearing parts are all made using specially hardened steel. The main lock body casing is reinforced for high protection against manipulation, twisting and lock-picking and has a modern, ergonomic design for easy use when handling, locking and storing.