Digital Pressure-Reference Gauge, RS232 PC-Interface Optional. Multi-function 4 Digit (5 @ 0.05%) LCD Display, w/ Back Lighting, Bar-Graph Min./Max. Values, Switchable Units,1/2" BSP St. Steel. Accuracy: +/- 0.2% FS, Zero Point: -1 bar (absolute). Interface: None. Includes SIKA Test Certificate.