Plug spinner

A plug spinner is a tool used to switch directions of a plug that has been picked in the wrong direction.

Variants
Gun Style Plug spinners visually resemble a Pick Gun, but apply high rotational torque rather than a strong snapping action. Their principal of operation involves putting the spinner into the keyway, squeezing a trigger and the plug turns to the opposite direction to which it was picked.
 * Gun Style

Several variants of the manual plug spinner exist, but most revolve around the concept of a tension wrench, with a spring rapped around it with one end of the spring attached to the tension wrench and the other with a small handle, the tension wrench is rotated in the opposite direction to the plug needing to be rotated while holding the small handle connected to the end of the spring in place. The end of the tension tool is placed into the keyway and the other end of it is let go of while the spring side handle remains stationary, causing the spring to retard the tension tool. Various tutorials exist that demonstrate making a plug spinner.
 * Manual