Protect your bike with Giant's SureLock Protector LS U-Lock. It boasts a heat-treated, hardened-steel shackle that's a half-inch thick, as well as a pick and drill-resistant keyed lock. It's 11.5 inches long, so you have room to add a wheel or your helmet. This tough lock includes five laser-cut keys, one of which features a powerful LED light. The shackle is vinyl coated so it won't scratch your bike and it comes with a handy carrying bracket that fits almost any bike tube so you'll never have to leave your lock behind.