Bullard Supplied Air Fitting Guide
The couplings pictured below are the most popular styles used on airline respirators. A coupling, which is made up of a socket (or nipple) and a plug (or coupler), is also called a "QD" fitting or just "fitting" and comes in various socket (female) and plug (male) sizes. Couplings can have male, female, or hose barb ends for different types of connections.
Industrial Interchange / Hansen-Compatible
Snap - Tite - Also known as Foster: "short and stubby"
Schrader - Looks like a bullet; turn the sleeve to release
CEJN - Similar to Hansen; two hands must be used to disconnect
Bayonet - Long and skinny with pins on the side; no ball bearings to trap grit. Popular with abrasive blasters
Dynaswivel - Swivels in two axes to keep from kinking
Industrial Interchange / Hansen- Compatabile
Dynaswivel with Industrial Interchange