Detailed Product Description Capsule Pressure GaugeDiameter: 4"Case: aluminumWindow: glassInternal: brassInlet thread: 3/8", 1/2", NPT, BSPT, BSPConnection: bottom connectionRange: -160~600MbarScale: psi, bar, Kpa, kg/cm2, Hg single or dual scale or according to customers order.Accuracy: 2.5%