The OnGuard Mastiff 4 ft Key Chain Lock provides dependable everyday protection for bicycles, e-bikes, scooters, and outdoor equipment. The 120 cm (4 ft) chain uses titanium-reinforced hardened-steel square links engineered to resist cutting, twisting, and leverage attacks in urban environments. Its integrated lock head features OnGuard’s X2P Dual Lock Down mechanism, securing both sides of the shackle to improve resistance against pulling and prying attempts. A double rubber-coated lock body helps absorb impacts and protect finishes, while the protective sleeve helps prevent scratches and shields the chain from corrosion and weather exposure. An automatic keyway cover helps block dust and moisture from entering the lock cylinder for reliable long-term operation. Includes five precision laser-cut keys.

• X2P Dual Lock Security: Integrated lock head secures both sides of the shackle to resist pulling, twisting, and prying attacks.
• Titanium-Reinforced Chain Strength: 120 cm (4 ft) hardened-steel square-link chain engineered for strong resistance to cutting and leverage attempts.
• Extended Everyday Protection: Medium-length chain provides flexible locking reach for bikes, racks, and fixed structures.
• Protective Weather-Resistant Sleeve: Durable cover helps prevent scratches and protects the chain from corrosion and outdoor wear.
• Complete Key Set Included: Comes with five precision laser-cut keys.


Manufacturer Sku: 8120
Todson Sku: 45008120