Working with pneumatic air lines? This Jienk set of 100 blanking plugs is incredibly handy for organizing and sealing your system. You get 20 plugs in each of five common tube sizes: 1/8 inch, 1/4 inch, 5/16 inch, 3/8 inch, and 1/2 inch outer diameter. They're made from PBT plastic and are designed for push-to-connect fittings - you just press the tube end into the plug to seal it off. They're perfect for temporarily or permanently closing off unused ports on manifolds, valves, or connectors to prevent dust from getting in and air from leaking out. Rated for air use up to 145 PSI. Having this assortment means you'll always have the right size plug on hand for any project, saving you time and preventing leaks. They're a small, inexpensive part that makes your workshop or pneumatic setup look more professional and run more efficiently. Essential for anyone tinkering with air compressors, tools, or automation projects.