These 3 mL capacity PYREX® Potter-Elvehjem tissue grinders (homogenizers) are used in preparing small samples for pathological and biochemical studies. Homogenization occurs as the sample and buffer are forced through the cylindrical portion of the mortar as the pestle is rotated downward. Mortar is not ground and the pestle contact surface is Polytetrafluorethylene (PTFE), threaded onto a stainless steel shaft. Caution: If used with a motor-driven device, the attachment must contain some form of friction release clutch to prevent damage to the apparatus from pieces of connective tissue or muscle. The user should wear a protective glove of sufficient thickness to prevent injury in the event of failure of the glass components.