The package includes 4 pressure gauges to help you monitor the air pressure accurately, our pressure gauge has an air pressure range of 0-200 PSI Pressure gauge replacement is suitable for measuring the pressure of air, fuel oil, oil, gas, water and other gases or liquids that do not corrode brass, and can be used to replace damaged pressure gauges on air compressors or compressed air tanks Our barometer 1/8 NPT is made of high quality materials including stainless steel bezel and case, brass connectors and glass lens, sturdy and reliable for long term use Our air gauges have an underside mount design that can be mounted on top of the compressor tank for easy reading, this feature ensures a seamless fit for easy installation and measurement Our air compressor pressure gauge is the perfect size with a dial diameter of approximately 1.57 inches / 4 cm and a thread diameter of approximately 1/8 inch, making it easier to read and take accurate measurements Colour:silver Material:Metal Package Contents: 4 x Air pressure gauges Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.