PresAir Trol Threaded 3 F Switch [Black Cam] [2 Microswitches] (MTK 211A) aandamfg Using the correct Eco 3 board Using the correct Eco 3 board helps keep the repair aligned with the intended system design and avoids unnecessary guesswork That combination supports a cleaner replacement path and helps the final result feel much more like a true restoration The PresAir Trol threaded 3 function switch with black cam and two microswitches is designed for compatible pneumatic control systems that require a more complex actuation arrangement in a threaded format Matching the proper cam and microswitch format helps preserve the way the control system was originally meant to operate