This shows a fridge thermometer with a scale marked in one degree C intervals from –30 °C to 40 °C. The bar of mercury stops at –4 °C. Shading shows that the three-star rating applies to temperatures from –30 °C to two intervals to the right of –20°C, the two-star rating to temperatures from the end of the three-star rating to two intervals to the right of –10 °C and the one-star rating to temperatures from –8 °C to zero.