20/410 Dropper Sets are Suitable for 20/410 MM Neck LGB Series Glass Bottles of Radcom Dropper assemblies are composed of a number of parts: the cap part is Inside Plastic fitted with Matt Silver ABS Sleeve Outside, the bulb (teat) and the pipette (tube). Dropper assemblies are used with liquids that require precision and intricacy when using the product Our Droppers Come with a Swabber Plug to Keep the Dropper Tube Clean and Straight in the Bottle to Avoid Any Impact Breakage During Transit of Final Product You Can Inform Tube Size When our representative calls for more Details below are available sizes for Glass Tubes