This high quality brass lock cylinder with Kwikset keyway has been specially milled, using CNC equipment, to reveal the top pins and springs as well as the actual shear line of the lock plug. Perfect educational aid for students and hobbyists, and perfectly functional as a practice lock for the development of crucial skills. Fits any of our practice lock stands, several of which can be found here on Bonanza. Pinned with a highly challenging 6-tumbler combination (each lock has its own combo, so if you purchase more than 1 you will receive locks with differing combos). We include 1 working key, and 1 key that will NOT operate the lock. This serves as a great visual aid and clearly demonstrates how pin tumbler lock cylinders work. It's invaluable as a learning tool. Brand new practice lock with complete instructions and tips, includes working key and non-working key for visual aid