John Guest Acetal Copolymer Barbed Tube Fitting, Stem, 3/8" Stem OD x 3/8" Hose ID (Pack of 10) Stem fitting for connecting pipes or tubes in a straight line Stem fitting inserts into tubing to connect pipes or tubes with different ends Made of acetal copolymer plastic for low moisture absorption and high tensile and flexural strength Working pressure of up to 150 psi Meets NSF/ANSI standards 14, 51, and 61 for quality assurance