Dust caps are one-piece blind nuts used to protect threads and keep contamination from cylinder valves. CGA thread specifications are used, but they do not make a gas tight seal.
Dust---Chain-Assemblies--Non-Gas-Tight-
Unit of Measure
1 

Item #

Item Name

CGA Standard

Application

Material

Connection

Part

CC-8021 N/A Dust & Chain Assembly (Non-Gas Tight) for Fuel Gas N/A 021 N/A Fuel Gas N/A Brass N/A "B" 9/16"-18-LH-INT N/A Cap Chain
CC-8020 N/A Dust & Chain Assembly (Non-Gas Tight) for Oxygen N/A 022 N/A Oxygen N/A Brass N/A "B" 9/16"-18-RH-INT N/A Cap Chain
CC-8034 N/A Dust & Chain Assembly (Non-Gas Tight) for Oxygen N/A 024 N/A Oxygen N/A Brass N/A "C" 7/8"-14-RH-INT N/A Cap Chain
CC-8035 N/A Dust & Chain Assembly (Non-Gas Tight) for Fuel Gas N/A 025 N/A Fuel Gas N/A Brass N/A "C" 7/8"-14-LH-INT N/A Cap Chain
CC-8300 N/A Dust & Chain Assembly (Non-Gas Tight) for Ethyl Chloride Acetylene N/A 300 N/A Ethyl Chloride Acetylene N/A Brass N/A .830"-14NGO-RH-INT N/A Cap Chain
CC-8320 N/A Dust & Chain Assembly (Non-Gas Tight) for Carbon Dioxide N/A 320 N/A Carbon Dioxide N/A Brass N/A .830"-14NGO-RH-INT N/A Cap Chain
CC-8346 N/A Dust & Chain Assembly (Non-Gas Tight) for Air N/A 346 N/A Air N/A Brass N/A .830"-14NGO-RH-INT N/A Cap Chain
CC-8350 N/A Dust & Chain Assembly (Non-Gas Tight) for Hydrogen/Methane N/A 350 N/A Hydrogen Methane N/A Brass N/A .830"-14NGO-LH-INT N/A Cap Chain
CC-8500 N/A Dust & Chain Assembly (Non-Gas Tight) for Medical Gas Mixture N/A 500 N/A Medical Gas Mixtures N/A Brass N/A .880"-14NGO-RH-EXT N/A Cap Chain
CC-8510 N/A Dust & Chain Assembly (Non-Gas Tight) for Acetylene/Propane N/A 510 N/A Acetylene Propane N/A Brass N/A .880"-14NGO-LH-EXT N/A Cap Chain
CC-8540 N/A Dust & Chain Assembly (Non-Gas Tight) for Oxygen N/A 540 N/A Oxygen N/A Brass N/A .908"-14NGO-RH-INT N/A Cap Chain
CC-8555 N/A Dust & Chain Assembly (Non-Gas Tight) for Propane for Liquid Withdrawal N/A 555 N/A Propane for Liquid Withdrawal N/A Brass N/A .908"-14NGO-LH-INT N/A Cap Chain
CC-8580 N/A Dust & Chain Assembly (Non-Gas Tight) for Argon/Helium/Nitrogen N/A 580 N/A Argon Helium Nitrogen N/A Brass N/A .960"-14NGO-RH-EXT N/A Cap Chain
CC-8660 N/A Dust & Chain Assembly (Non-Gas Tight) for Regrigerant Gases N/A 660 N/A Refrigerant Gases N/A Brass N/A 1.035"-14NGO-RH-INT N/A Cap Chain
Unit of Measure
1