The screamer disc lock emits an ear piercing 100db alarm to deter would be thieves the 7mm locking pin fits through the holes on the brake discs on most modern bikes and the lower section is chamfered for easy fittingthe thatcham institute for vehicle security is recognised by insurers as the ukrsquos leading tester of vehicle security products products with the thatcham label have been demonstrated to comply with the british insurance industryrsquos criteria for vehicle security the to