On-Guard (Magnum) locks set a new standard in bike security with unprecedented levels of strength. Comfortably exceeding test norms, these shackle locks are made of hardened ultra steel, delivering up to 10 tons of pulling resistance. Multi-position, q/r mountings and 5 keys add to the appeal. High security padlock and chain models have deadlock bolting mechanisms to defy the most persistent thieves. Heavy duty self coiling cable locks are every bit as well made, albeit at less cost offer lower levels of security.