Bronze bourdon tube 270 degree sweep movements and durable nylon gearing make rugged and long lasting gauges a proven high performance favorite for over 25 yearsRequire no electrical power for operation and indicates oil/waterIdeal choice for vehicles with no or low powered electrical systemsIncludes 1/4 inch, 3/8 inch, and 1/2 inch NPT adapter/fittingIncludes 6 ft tubing and includes 1 ft nylon tubing with 1/8 inch NPT fittings