An end effector for handling stacks of plastic cups, dishes, and similar items. The end effector includes a bracket for coupling the end effector to the end of a robot arm. A main plate or body with a top side, a bottom side, and a plurality of apertures is connected to the bracket and supports the major components of the end effector. The end effector includes at least one bay positioned in the bottom side of the main body. Within each bay is a multiple-piece blade support block that helps guide the blades located within the bay. One or more roller blocks are positioned at predetermined points along the length of the bay, preferably between two pieces of the blade support block. Each roller block has an arcuate track that holds a roller assembly. Each roller assembly has a link which extends through one of the apertures in the main body. Each roller assembly is also coupled to a curved blade. One or more linear actuators are positioned on the top side of the main body. The driven rod of each actuator is coupled to one or more of the roller assembly links. When the actuators are activated, the roller assemblies move in their tracks and the blades slide between an open position and a closed position.