Features Excellent replacement for the old or broken check valve of your air compressor The three male thread connectors are respectively for tube connecting, air Thread Diameter: 9.5-10mm 16-16.5mm 20-20.5mm; Male Thread Size: 1/2" 3/8"; Hex Head Size: 18mm. Convenient to install this air compressor accessory with the thread connecting ends Material: Zinc Alloy. Heavy duty constructed air compressor check valve is durable and long lasting. Features: Excellent replacement for the old or broken check valve of your air compressor. The three male thread connectors are respectively for tube connecting, air. Convenient to install with the thread connecting ends. Specifications: Product Name: Air compressor Check Valve Material: Zinc Alloy Color: Golden Thread Diameter: 9.5-10mm 16-16.5mm  20-20.5mm Total Size: 42 x 39mm Male Thread Size: 1/2" 3/8" Hex Head Size: 18mm Note: Please allow a little size error due to manual measurement. Package Included: 1 x Air Compressor Check Valve Package List