Our 2126-M is a dual scale mechanical gradiometer with warning zones. The bottom scale is ±26 degree scale with 2 degree increments. The top scale is ±45 percent grade with 5 percent increments. The color zones span from 25 to 45 percent and 14 to 26 degrees respectively on each side. The housing is made of rugged ballistic plastic, making these gradiometers extremely tough for all types of environments and weather conditions. With operating temperature ranging from -45°C to 82°C the 2126-M is the perfect all-season gradiometer. The large, clear number and degree markings make it easy to get quick, accurate readings.