This is a hand operated pull through type coupling expander that is designed for small production runs or manual repairs of sizes 5/8" to 2" as a guide and depending on model and drawbars. Each size requires a pull through punch (listed below) and a threaded 2" female reducer pipe coupling (ie. our N250-200-xxxBI) to attach to all male NPT ends before pull through. If attaching N96- "female" Scovills, then a N200-xxxBI close nipple is also required. Instructions are provided with machine.