GM TH700R4, TH200, 200-4R, TH350 and 4L60 Transmissions. The B&M converter lockup controller provides dash-mounted control to govern converter lockup at any speed between 30 and 90 mph. These kits eliminate converter lock and unlock cycling and premature unwanted converter lockup. Works with GM automatic transmissions using a lockup style torque converter and a mechanical speedometer. GM TH-700, 200, 200-4R, 350 and 4L60