Designed for a variety of compression applications. Works on conventional, electronic and computerized systems on both foreign and domestic vehicles. Large 3 1/2in. gauge with protective housing. Dual-calibrated and color-coded scale. Side-pressure relief valve and quick-connect/disconnect coupler attached. 24in. high-pressure flexible hose with 1 4/18mm adapter. Not designed to work in diesel engines, only on spark-ignited gasoline engines where cylinder pressure does not exceed 25 PSI. Also includes 14mm long-reach, 12mm and 10mm adapters. Comes in convenient plastic carry case for storage. Model #3214.