Betts Interference Control Valve works as an two-way spring return dump valve for a truck’s air system by trapping downstream pressure if the supply pressure is maintained and not exceeded.  Valve is normally closed, and depression of the piston by a truck cabinet door or other means releases the air pressure.  This can be used to close all emergency valves simultaneously. Ports are 1/8″ NPT and #10-32 female.  Flow rate is 7 CFM at a max pressure of 125 psig.

Assembly number is IC17128BR.