You would need an adapter to use the Prodigy RF brake controller # TK94FR with a 7-Way round pin connector such as # HM47425. The issue though is that if your 7-Way round pin is on a big rig type of vehicle it will not have the same functions as a trailer type of 7-Way round. The easiest solution to this is to install a separate 7-Way blade style connector on the tow vehicle such as # 37185. view full answer...