3 in 1 multifunctional and easy to use: This is a pressure gauge for precise monitoring of tire pressure. It also functions as a tire inflator when connected to an air compressor. Additionally, it features a built-in vent valve for quickly releasing pressure from overinflated tires. High accuracy: Professionally calibrated to provide readings within 1% of actual tire pressure with a 0.1 PSI resolution. Measures accurately from 0 to 250 PSI (0-17.2 bar; 0-1724 kpa; 0-17.5 kgf/cm²). Waterproof design with automatic shut-off and valve extension. The quick-locking air line (push-fit gas interface) ensures a secure seal on tire valves and allows hands-free operation while using a tire pump. Long service life: Constructed with high-quality stainless steel and brass components for durability. Compatible with various vehicles including cars, SUVs, trucks, motorcycles, and bicycles. Automatically powers off after 20 seconds of inactivity to conserve battery life. Integrated vent valve allows for rapid pressure reduction in overinflated tires. High-quality construction: The device has a solid feel due to its use of premium stainless steel and brass, designed to withstand pressures up to 250 PSI. The rubber hose is insulated and extra thick for enhanced performance. High precision 250 PSI tire pressure gauge. Measuring range: 0-250 PSI. Accuracy: ±1% + 0.1 PSI. Displays readings in four units: PSI, BAR, KPA, KG/CM². Button functions: On/Off button (left), unit switch/LED light (right). Compatibility: 1/4 NPT air compressor connection (included). Operating voltage: DC 3.1 V (2 AAA batteries included). Instructions: 1. Remove the valve cap from the tire. 2. Attach the brass head of the gauge to the tire valve. 3. Read the pressure displayed on the screen. 4. Connect an air compressor hose to the inflator port if inflation is needed, or use the built-in bleed valve to release excess pressure. 5. After use, remove the gauge and press the bleed valve to reset the display to zero. Included accessories: 4 valve caps, 1 brass air chuck, 2 AAA batteries, 1 NPT steel fitting, 1 roll of thread sealing tape, 1 pneumatic rotary chuck, 2 sealing O-rings.