Marketing InformationThe Check-Trol™ flange is a combination of isolation valve, flow control valve and companion flange for circulators. The ball valve allows the circulator to be removed from the system without draining the system. The internal spring check prevents gravity circulation. Free floating companion flange makes pump installation a snap. The Check-Trol™ flange is packaged with an isolation flange of the same size to create a pair. Cap screws and nuts are included.