1/4 in. Fittings Male Pneumatic Plug - AndyMark, Inc
Threaded Straight Through Pneumatic PU Air Pipe Quick Plug Solenoid Valve Connector – Inosaki
Amazon.com: uxcell Push to Connect Fittings, Cap Style Pneumatic Blanking Plugs, Fit for 6mm Inner Dia. Air Hose Tube Pipe, Plastic, Black, Pack of 20 : Industrial & Scientific
Pneumatic plug 1/4" MALE NPT | GW Kent
Parker Interchanges Tru-Flate, Steel Male Plugs 3/8" x 1/4"
10X Blue Nylon Pneumatic Blanking Plug Hose Tube Push Fit Connector Air Line 4/6/8/10/12MM - AliExpress
Actuated Plug Valves - Omega Valves
1/4 Inch NPT Plug Male Female Industrial Air Plug, Male Coupler, Pneumatic Plugs, Quick Connector Air Fittings Kits(1/4'' F-NPT) - Amazon.com