Check the listing for details. Tesi OTTO/L 12mm Latching Stainless Steel Guitar Toggle Kill Switch. Condition: New. Listed at 12.99 USD. Tesi OTTO 12MM Toggle style Kill Switch is a quick and easy modification. The switch itself is heavy duty and built to last. It functions like a standard on-off switch. If you're looking for the OTTO switch with automatic return, search TESI OTTO. The switch is easy to install. If you have the slightest bit of skill with a soldering iron you can do it yourself. If you do not have that skill, you should have a guitar repair person do it. The mounting hole is slightly larger than a standard volume or tone pot (12MM vs. 9MM). The Tesi OTTO/L will work with any pickup configuration. Just solder one pole to the hot pickup signal wire and one to the ground. The switch includes:(1) Tesi OTTO/L switch with the proper wiring already attached(1) Set of easy-to-follow wiring instructions Thanks for checking out the Tesi Kill Switch!