Abstract: A material transfer system for loading lightweight granular plastic material into injection molding machines and the like includes a reservoir sight glass assembly connected to the associated machine and a lightweight pressure relief chamber attached to the reservoir sight glass assembly, both connections being by quick disconnect devices. The reservoir sight glass assembly includes, a sensor which responds to the level of material in the sight glass and a magnet assembly which traps ferrous contaminates and prevents their entering the machine. The flow of material to the pressure relief chamber is controlled by the sensor which turns a regulated source of compressed air on or off depending upon the level of material in the sight glass. The air source is connected to an accelerator and vortex unit which is, in turn, connected to a source of the material.