a material handling conveyor comprising an overhead conveyor which supports containers or magazines for the material . the magazines have top and bottom openings and a closure for each which includes a closure mechanism having a movable lever . the first part of the movement of said lever effects the closing of the magazine and the last part of the movement of said lever clamps the closure down tight on the magazine to provide a leakproof seal . the entire area of the magazine which is in contact with the material being carried is made of an inert substance such as stainless steel or a plastic which is supported by a frame made of a stronger substance which also carries the full weight of the magazine and the material being in the magazine , thereby relieving the inert substance part of the magazine from carrying the load which enables that part to be made of lighter construction .