The OnGuard Mastiff 3.5 ft Chain Lock is built for serious security in medium-to-high risk areas. Its 1090 mm (42.9 in) titanium-reinforced hardened-steel hex chain integrates directly into an X2P Double Bolt Lock Head for exceptional pull resistance. The advanced Z-Cylinder protects against bumping, drilling, and picking, while the dual rubber housing shields paint and finishes. Perfect for bikes, scooters, and e-bikes, this lock balances strength, durability, and ease of use. Includes five laser-cut keys, one with an LED light. Weighs 5.7 pounds. High-Security X2P Head: Integrated X2P Double Bolt Lock Head provides extreme pull resistance and features a dual rubber housing for added impact and weather protection. Heavy-Duty Steel Chain: 1090 mm chain made from 10 mm hardened-steel hex links delivers superior cut, pry, and leverage attack resistance for confident daily protection. Weighs 5.7 pounds. Built for Riskier Areas: Ideal for medium-to-high threat environments, offering reliable defense for bikes, e-bikes, scooters, and motorcycles during everyday use. Advanced Z-Cylinder Core: Precision-engineered locking cylinder resists drilling, bumping, and picking, ensuring long-term reliability and theft prevention. Includes Five Keys: Comes with five laser-cut keys-including one LED key-offering smooth operation and excellent visibility for night-time use.