If this ever happens to you. Call us first, we can pull the broken key out of the cylinder and make a duplicate copy on the spot. Make sure you have the other piece as it makes the process easier to dupe. Call All City Locksmith of Rancho Cucamonga today for all your key needs. We offer commercial, residential, automotive and emergency lockout assistance. Serving Rancho Cucamonga and the surrounding areas. The Most trusted locksmith in the Inland Empire and with the most Yelp Reviews.