This is a polypropylene, stable, non-corrosive, detachable stand, which can hold 28 pipettes with a maximum diameter of 9/16". The heavy base measures 9" in diameter and a polypropylene coated square rod measuring 15" in length is screwed into the base. The top disc has holes for holding the pipettes while the lower one has pilot holes where the pipette tips rest and liquids drain down to the base. Both discs can be moved up and down the rod to accommodate various lengths of pipettes. The arrows provided on the discs should be kept parallel to ensure that corresponding holes are being centered.