Multi Stage Restriction Orifice Plate Assembly devices are used where the pressure reduction ratio is very high and cannot be achieved by a single stage orifice plate. Thus a multistage device essentially consists of a number of single stage device built in a single spool. Like a single stage device it can be of single hole multi stage design or multi-hole multi-stage design or combination of both.

The Restriction Orifices are arranged in eccentric manner, diametrically opposite each other during fabrication of MRO.