Y787 Smart Alarm Lock Antitheft Chain Lock For Bike Gate Blue f54 1Alarm immediately when cutting steel rope or removing lock screw. 2Alarm immediately when shaking or moving the lock. 3Call the police immediately if you mistype your password three times. 4Drawing out the wire rope can be used as a defensive whip, wire rope diameter 10 mm, length 80 cm (optional 40 cm/1.2 m). 5Fourdigit passwords with 256 password combinations.Features:Alarm immediately when cutting steel rope or removing lock screw. Alarm immediately when shaking or moving the lock. Call the police immediately if you mistype your password three times. Drawing out the wire rope can be used as a defensive whip, wire rope diameter 10 mm, length 80 cm (optional 40 cm/1.2 m). Four-digit passwords with 256 password combinations. Lock/unlock button operation, no key required. Powered by three AAA No.7 batteries, 8 months standby time and have low power indication function. IP44 waterproof certification, suitable for indoor and outdoor use. It can be used normally at temperatures ranging from - 20 to + 60. Over 110 decibels of alarm sound. Specifications:Power Supply: Three AAA Batteries (Not Included)Battery life: standby mode, about 8 months or moreSpecification of steel rope: diameter 10 mm, length 80 cm (optional 40 cm, 1.2 m)Chain Specification: 6mm in diameter and 80cm in lengthOperating temperature: - 20 ~60Storage Temperature: -30 ~+80 Size: 9.2*5.5*3.4cm/3.6*2.2*1.3inPackage Weight: 300g/10.6ozPackage List:1 * Lock (Batteries Not Included)1 * Screwdriver1 * User Manual