Pipette tips, sometimes spelled pipet tips, are used with pipettes and pipettors to speed processing and reduce cross-contamination. They are available in a variety of materials and styles. Universal pipette tips are uses with most standard-diameter pipettes. They are usually made of polypropylene and disposable. Glass pipette tips are used in applications where harsh chemicals are dispensed or in use. Other styles include specialty tips for tasks such as gel loading, filtering tips for reduced risk of cross-contamination or damage to equipment, robotic tips for use with automated pipetting systems, and micropipette tips for use with micropipettes. Features to consider when selecting a pipette tip include volume capacity, sterile or non-sterile requirements, and racking.