Easy-Vent Nipple Plug for accurate readings every time.
Marshall shock-proof pressure gauges have rugged construction and are liquid filled for vibration dampening. Read instructions carefully before installing. IMPORTANT: Ensure accurate readings by venting the gauge. Install gauge so that the nipple plug is facing up. Once installed, cut the nipple on the plug. This allows the case to be vented at all times ensuring an accurate reading without additional venting/cooling. DO NOT cut the plug nipple if the plug is not facing up. If you do not cut the nipple plug you will need to vent or cool the gauge each time you take a reading to ensure an accurate reading. See http://www.marshallinstruments.com/faqs/ for more information.