Superior Tool 17660 6-In-1 Swaging Tool Swaging tool Join similar size copper tubing without couplings Insert tool into copper, brass or aluminum tubing and strike with hammer Only one solder joint required Join similar size copper tubing (3/16&#034; to 5/8&#034; ) without couplings: just insert tool into copper tubing and strike with hammer Only one solder joint required Cost-effective--saves material. Heat treated alloy steel