Rekeying Keying tool for on-site use with Universal Pin Padlocks.  This tool pins a lock in seconds by cutting off the segmented pins to match the depth of the new key.  Requires a hammer and vise to hold the lock.  Only works with unkeyed Master Lock Universal Pin Padlocks.

Here are the steps:

1. Secure an unkeyed Universal Pin Padlock in the vise (cylinder facing up)
2. Position the tool over the key you would like to key the cylinder to
3. Strike the tool, setting the cylinder flush with the body of the lock