Abstract: A canister set for dispensing measured amounts of flowable solids has a common support. Each canister of the set has a removable trap chamber for residue solids which may be cleaned out at intervals. The trap chamber of each canister is engaged by a receiver vessel and shifted to a material dispensing position. A mechanism on each canister is engaged and activated by the movable trap chamber to shift a closure slide at the bottom of a material measuring chamber to an open dispensing position where the flowable solids can gravitate into the receiver vessel. Substantially simultaneously an upper closure for the measuring chamber cuts off the flow of material thereto from an overhead storage hopper during the dispensing operation. A spring automatically returns each trap chamber and associated mechanism to its normal position.