Master locks are junk. It is consumer fraud for Master lock to call their products "locks". Their cuffs last just slightly longer than a shoelace, against a thief who understands its flaws.

If you live in a major USA city or park on a college campus, and leave your bike out of your sight for more than ten minutes at a time, you need a SERIOUS lock. A serious lock is one that has earned a "gold" rating from Soldsecure, based on testing by their locksmiths.

www.soldsecure.com/Leisure.htm