Ideal Vacuum | Sample-Seal U-Tube Liquid Sample Holder 100 ml, 5/8 in. OD, Adjustable 0-4 mm Valve, Teflon Tip, High Vacuum Valves, 6.35mm Glass, Includes two 0-4 mm High Vacuum Valves with
SR Aquaristik Glass U Tube for Aquarium CO2 Tubing – zooxae.com
Ideal Vacuum | Sample-Seal U-Tube Liquid Sample Holders, 5/8 inch OD, HV Valves, #15 O-ring Joint Flanged Includes two 0-4 mm High Vacuum Valves with O-Ring on Tip., High Vacuum Storage Sample
Amazon.com: DADAKEWIN 13 * 100mm Drying Tube U-Shaped Glass Tube for Air Drying, Borosilicate 3.3 Glass Heavy Duty Customizable Lab Tubes- Pack of 1 (Color : 13 * 100mm) : Industrial & Scientific