P SERIES: Available in tapered and straight styles, Caplugs P Series Plastic Threaded Plugs for NPT/NPS Pipe Fittings are red-colored plugs designed to seal the threaded ends of pipe fittings, protecting the internal threads of the fittings from dust, dirt, debris, moisture and other pollutants MULTI-USE: Our P Series plugs can be utilized in a multitude of industries for various processes and applications, such as masking, painting, plating and coating, and for temporary sealing of threaded ends during assembly and testing of pipe fittings, transportation and storage of fittings and during pipe and valve maintenance. SEVERAL STYLES AND SIZES: Caplugs P Series Plastic Threaded Plugs for NPT/NPS Pipe Fittings are offered in different sizes and six different styles to fit tapered (NPT) and straight (NPS) threads. This specific model P-28 (99390174) fits the following thread style and size: NPT 1/4" STRONG AND DURABLE: Caplugs P Series Plastic Threaded Plugs for NPT Pipe Fittings are constructed from high-density polyethylene (HD-PE), a lightweight thermoplastic polymer known for its high strength, density and durability. It is exceptionally resistant to a wide range of chemicals, including acids, bases and solvents, as well as resistant to environmental stress cracking and corrosion. It has a service temperature range of 0° F (-18° C) to 215° F (102° C). PARTS YOU CAN TRUST: Caplugs prides itself on its extensive line of premium products that are suitable for a plethora of industries, from aviation to medical, general manufacturing and everything in-between. At Caplugs, we provide the broadest range of solutions and the highest quality parts right when you need them. Our teams work diligently to ensure consistent results, with more engineers on staff, processes for creative solutions and molding experts for reliable quality.