PROCESS LEVEL ACCURACY: Each ETENWOLF’s digital tire pressure gauge is calibrated manually to ANSI B40.7 Level Grade 2A(plus-minus 1 PSI)ated to ANSI B40.7 Grade 2A(plus-minus 0.5%), Replaceable AAA Batteries ACCURACY IN EXTREME WEATHER: Built-in AI chip with thermal compensation inside, ETENWOLF’s tire gauge works normally even in extreme cold or hot weather(-4°F-130°F/-20°C-54°C) ACCURACY IN EXTREME PRESSURE RANGE: Whether tire pressure is below 12 PSI or above 140 PSI, ETENWOLF’s digital tire gauge is accurate as well PRESSURE RANGE 3-200PSI : ETENWOLF’s digital tire pressure gauge can measure pressure of all types of vehicles REPLACEABLE AAA BATTERIES: Batteries are easy to replace and helps to extend the tire pressure gauge’s life span, backlit LED display and lighted nozzle make it visible in dark areas