mpo55Danfoss MP 55 Differential Pressure Switch is used in refrerating systems with R717 and also systems with HCFC and non-flammable HFC refrerants. MP 55 Pressure Switch has a fixedThe MP55 is a ranged weapon that fires 10mm Rounds. It can only be equipped in a Primary Slot. The MP55 is a German selective-fire, magazine-fed, 10mm submachine gun. It fires up to 30