The CrimpRite 1/2" and 3/4" combo crimp tool is a 2-in-1 tool designed to secure 1/2" and 3/4" copper crimp rings into place within PEX piping systems. There are no loose components, jaws to change, or adjusents to be made to create either size connection. Connections may be checked for security using the Go/No-Go Gauge (included). Twelve (12) 1/2" copper rings and six (6) 3/4" copper rings are also included.