8170D U-Lock Bike Lock, 1/2 In. Shackle, 6-1/8 In. Wide

The Master Lock 8170D U-Lock is a hardened steel bicycle security lock designed to protect your bike from theft in urban and high-traffic environments. Built with a reinforced steel construction, this U-lock resists common hand tools and brute-force attacks, giving cyclists peace of mind whether they're commuting through city streets or securing their bike at a weekend destination.

This compact yet robust lock combines portability with serious anti-theft protection. The integrated mounting bracket allows you to carry it conveniently on your frame or bag, so you always have security within reach. Whether you're locking up for minutes or hours, the Master Lock 8170D delivers the durability and reliability that cyclists depend on.

Features and Benefits

• Hardened Steel Shackle: The 1/2 inch diameter double-locking shackle is made from hardened steel, providing superior resistance to bolt cutters, prying, cutting, and sawing.
• Disc Key Cylinder: The precision-engineered disc key design prevents picking and adds an extra layer of anti-pick security, ensuring only you can unlock it.
• Compact Construction: The 6-1/8 inch wide body with an 8 inch long shackle delivers serious anti-theft protection in a size designed for bicycle security.
• Included Mounting Bracket: Simplifies attachment to your bicycle frame or backpack for convenient transport and quick access when you need it.
• Master Lock Brand Reliability: Backed by decades of lock-making expertise, this lock is supported by a limited lifetime warranty for trusted, long-term performance.

Specifications

• Brand: Master Lock
• Model: 8170D
• Body Width: 6-1/8 inches
• Shackle Diameter: 1/2 inch
• Shackle Length: 8 inches
• Shackle Material: Hardened steel, double-locking
• Body Material: Hardened steel
• Key Type: Disc key cylinder, keyed different
• Warranty: Limited lifetime warranty