1. Size and quantity: Height: 2.3cm diameter:1cm 4pcs in one package
2. Material and application: stainless steel copper core american valve cap applicable for universal bicycle car
3. Function: Simply install on the air valve. According to the recognized color to display the pressure of the tire red and yellow indication bar: tire pressure at below 2.0 Bar (Less than 75% of the standard) DANGER; Yellow and Green indication bar: tire pressure at 2.3-2.0 Bar (Less than 90% of the standard) WARNING; Green indication bar: tire pressure at normal range 2.4 Bar SAFE.