These multi-purpose vials are ideal for RIA, sample storing or culturing, liquid scintillation or gamma counting, and chromatography applications. Exterior press-fit polypropylene cap permits total use of vial capacity and protect hands from contents. Smooth interior surfaces allow for easier transfer and pipet access. The 4 ml vial is autoclavable polypropylene. The 6 ml size is high density polyethylene with a white polypropylene cap. Cat. No. 957-200-15 has a hanging cap which allows vial suspension and easy access when used with Wheaton glass and PET, 20 ml liquid scintillation vials with 22 mm neck size.