Features and Benefits: Professional timing light with high visibility LED display; Very bright display indicates: - Tach (RPM) - Degrees Advance; Measures ignition spark advance from 0-90 degrees; 2 and 4 Stroke Tachometer measures engine speed up to 9,000 RPM; Detachable and replaceable cable set; Professional timing light with very bright LED digital display of RPM and Advance. Pushbuttons on the control panel change the mode, increase/decrease advance degrees and switch between 4 and 2 cycle. Designed for precise tuning and diagnostic work. Unit is accurate to 9,000 RPM and works with 12 Volt systems.