3-3/4in. 8000 RPM Tachometer features a polished chrome finish. State-of-the-art air core movement ensures accurate readings and quick pointer response. These tachs operate on 4, 6, or 8 cylinder engines with standard, electronic ignitions with 12 volt power. Dial face dia.=3-3/4in., Bezel dia.= 4-3/8in., Case dia.=3-3/4in., Case depth=3-3/4in. Allow 1in.-3in. for Fittings & Tubing.