Fangrui Product Details You Get 25 Pieces Pipe Fitting Assortment Kit In 5 Sizes, Npt 1/8inch, Npt 1/4inch, Npt 3/8inch, Npt 1/2inch, Npt 3/4inch, 5 Pieces/size, Storage In A Box For Your Industrial Needs. Made From Great Brass With Superior Acid-resistance, Anti- And High Strength, Strong Texture, High Hardness, Standard Thread, Not Easy To Slip. A Mechanical Fasteners, The Role Is Sealing. Male National Pipe Taper (npt) Threads For Using With Female Threaded Pipes; Male Pipe Threads For Connecting To Female Threaded Pipes Or Fittings. Hex Threaded Head Design For Quickly Installation And Removal. Suitable For Closing The Ends Of The Pipe Or Tube. Countersunk Plug With A Hex Drive For Closing Of A Pipe Or Fitting. 5 Sizes Pipe Plugs For Different Needs. Not Only Work Great On Preventing Leakage Of Air, Steam, Gases, Water, Oil And Fluids Under Pressure, But Also Great For Blocking Off Intake Manifold Water Ports, Water Pump Ports, Water Temp And Oil Sender Holes, Engine Block Holes, Etc. No Gasket Required For These Npt Threa