Also sometimes referred to as a “T-Pin Connector”, “Dropline Tee”, or “3-Way Tee”.
AKA Dropline Tee Connector
This fitting allows you to join a 3/16″ drop line to a 3/16″ lateral line. At the end of the season, use the pin to hold/store each tap. This will cap off the drop line and prevent debris from getting into your tubing system during the off season.