SAVES TIME AND MONEY: Don't waste time and money on expensive and complicated tread depth measuring devices. With the VERGO depth gauge, it only takes a few seconds to check the condition of the tires. Check and go HIGH PRECISION: This gauge measures in 1/10mm (0.1mm) increments. EASY TO USE: The diameter of the dial is 2inches (5cm). The clear and precise reading facilitates the use. No special experience or skills are required, the gauge is designed for everyone. The color code is easy to read. Tissue pouch included: Easy to store and carry in the velvet fabric pouch No batteries needed This is how you read the color code: Zone 1 (red) shows tire tread is deteriorated/worn tire needs changing Zone 2 (yellow) shows marginal tread remaining tire needs changing soon Zone 3 (green) shows that the tire has ample tread the tire is safe to use High accuracy: Gauge measures in 1/10mm (0.1mm) increments.Solid Gauge - Indicator has a solid zinc cast body with acrylic lens Manual Reset - The reset of the gauge is very easy and it takes no effort: the dial hand returns to 0 (zero) by pushing the rod back by hand, or by gently pressing the rod against a flat surface (e.g., table) Measurement system - Metric (mm Scope of delivery: 1 piece Product color: white Product size: 6*5*2.3cm Note: Manual measurement, please allow 1 - 3cm error