Dispensing Bottle, Screw Closure Size 28mm, Autoclavable No, Sterile/Non-Sterile Non-Sterile, Pre-Cleaned None, Closure Material Polypropylene, Special Features Dispense Desired Volume of Liquid By Squeezing The Bottle, Excess Liquid Returns to the 500ml Bottle for Spill Free Pouring a Hollow Stopper Dust Cover is Included, Forcing Liquid Through The Tube Into The Graduated Cup When Pressure is Released