It is made of acetal copolymer plastic, which has low moisture absorption, high tensile and flexural strength, and is hard and fatigue resistant. The working pressure for this fitting is up to (150) per square inch (psi), Food equipment materials, and use with drinking (potable) water. Pipe fittings are components used for connecting, terminating, controlling flow, and changing the direction of piping in many different industries. Push-to-connect compression fittings do not require tools or sealants, and are useful in installations where a heat source, such as a soldering torch, is prohibited. When purchasing pipe fittings, consider the application, as this will affect material type, shape, size, and required durability. Fittings are available threaded or unthreaded, in many shapes, styles, sizes, and schedules (pipe wall thickness). Push-to-connect fittings and pipe and plastic plumbing systems.Pre Elbow Connector Suited for RO model which uses 1/4"" Size Tube. ( pack of 30 Pieces )