Review on Fenix AER-02 Remote Switch: Optimal Control for TK09, TK11R5, TK12, TK15, TK21, TK22 & PD35 Flashlights by Brian Piecuch

Someone posted on another Amazon forum that it doesn't fit the UC35, mine fits perfectly. The tension of the spring is quite strong, at first I didn't think it would fit until I felt the threads connect. The cord is unnecessarily long, but can be easily fixed with a retaining strap. Both pushbutton switches work properly, the round one toggles on/off and the long one only stays on when pressed. The delivery was faster than expected, 10-12 days faster than stated.