AmazonBasics B005PJJ89U Manual De Instrucciones página 7

2. Press Set again and hold for 3 seconds. The unit "PSI" or
"BAR" appears and blinks. Press or  to switch between
PSI and BAR. Then, press Set to confirm your selection.
The icon indicating front or rear tire lights and blinks.
3. Press or  to choose front or rear tire, then press Set to
confirm.
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