The in-line air flow regulator is used for connecting threaded pipes and hoses, high-quality construction for maximum strength and durability. Can easily control the speed of the flow. However, does not stop the air/flow 100%.Specification:Product Name: In-Line Air Flow Regulator.Connector Type : 1/4" NPT Male & 1/4" NPT Female.Size: L X W: 40 x 25 mm / 1.57 x 0.98 inch.External thread diameter: 13 mm / 0.51 inch.Internal thread diameter: 12 mm / 0.47 inch.Material: Iron.Color: BlackYou will receive:2 pcs 1/4" NPT male & female in-line air flow valves.