B&M Dash Mounted Converter Lockup Controller GM 700R4/TH350C/4L60/200-4R Automatic Transmissions

For use on GM transmissions, these converter lock-up controllers prevent converter lock, unlocks cycling and governs lock-up at speeds ranging between 30 and 90 mph. Designed to eliminate premature, unwanted converter lockup so you can avoid engine lugging and spark knock. In addition, you can use the controller for converter lock-up operation when converting a non-lockup equipped vehicle to a lock-up style transmission and converter.