Dispensing caps from Qorpak are widely in the pharmaceutical and food industries for dispensing small amounts of liquid. Also known as dropper assemblies, these units feature a glass tube that has a black polypropylene closure and a convenient rubber squeeze bulb. The polypropylene material closure is semi-rigid and offers good chemical & fatigue resistance. These caps are provided in packs of 12. The standard GPI thread finish for Qorpak dropper caps is 400 with a neck finish of 20-400 or 22-400. Choose from a broad range of these caps, available in mouth diameters of 20 and 22 mm on Raptor Supplies.