Popper Micro-Mate® Interchangeable Syringes are manufactured to insure the perfect mating of barrels and plungers. Any Micro-Mate® interchangeable syringe of a particular size will fit any Micro-Mate® barrel of that same size for true interchangeability. These syringes are made from superior Borosilicate resistance glass, and the excellent physical-chemical property of the glass provides protection against thermal shock and corrosion resistance. All of the syringes are re-usable and autoclavable, easy to clean, and have permanent, fused-in graduations. Center Metal Tip.