Alarm Padlock 100db siren alarm padlock When the deep groove on inside edge of the shackle is fitted with the groove on the the key port side of the lock the alarm is active If shackle is fitted other way round the alarm system is inactive The alarm will sound for ten seconds if activated and will reset after thirty five seconds without a trigger Supplied with three keys and six LR44 button cell batteries Hasp diameter of 10mm, Manufacturer: Rolson