The Quick Rack System Pipette Tips Refill are accurate and reproducible. Manufactured from the latest polymer resins with tapered orifice technolgy to assure the best liquid handling perfomances. It is certified to be free of Rnase, Bnase, Human DNA, pyrogen (endotoxin), and PCR inhibitors. This high-grade polypropylene polymer resin is low-binding, antistatic, autoclavable, and nucleated. Available in different volume capacities.