The Pneumadyne Inc. Inline Check Valve is a brass body valve with a 1/4" NPT female inlet and outlet. It has a cracking pressure of 1 psi and a maximum pressure rating of 250 psi. This inline check valve allows flow in one direction but prevents reverse flow. It can be used in air, water, oil, and inert gas applications. The valve body measures 1-1/4" long x 7/8" wide. Made in the USA.