Mechanical gauges are accurate but can be a safety hazard. Whether monitoring fuel, oil, or coolant pressure, you can do so without the risk of spraying fluid all over your interior. Simply connect a pressure line from your engine compartment to one side of the pressure isolator, and then fill the line from your gauge to the other side of the isolator with a 50-50 mix of antifreeze and water. Your gauge will read pressure instantly, accurately, and safely. This kit includes an isolator, mounting brackets, and -4AN fittings. Compatible with gasoline, alcohol/methanol, oil, and coolant.