Tissue Grinders are used for the controlled reduction of particle size and homogenization of a variety substances, especially biological material. Size reduction/homogenization is brought about by the shearing forces generated by the movement of a rotating plunger in a precision bore tube. Determining factors include clearance between plunger head and tube, speed of rotation and viscosity of medium. The plunger head is pure PTFE and shaft is stainless steel, Ø6.5mm. the tube is precision borosilicate glass and the clearance between the plunger head and tube 0.15-0.25mm. Other clearances are readily available. Volumes stated are working volumes with the plunger in place.