110db twin tone siren alarm padlock Alarm sounds for 10 seconds & resets after 35 seconds Supplied with 3 keys & 6 x LR44 batteries There is a deep groove on the inside edge on one side of the shackle. When fitted with the groove on the key port side of the lock the alarm is active. If the shackle is fitted the other way round the alarm system is inactive. The alarm will sound for ten seconds if activated & will reset after thirty five seconds without a trigger.