In addition to its ranging capability of 1,000 yards, the ProStaff 1000i is equipped with ID (Incline/Decline) Technology to ensure accurate horizontal distances even when ranging at various incline or decline angles - up to A 89 degrees, nearly vertical up or down! Tru-Target Technology allows you to choose between First Target Priority Mode for the distance to the closest object among a group of targets or Distant Target Priority Mode which ranges the farthest target in a group of targets. Measurements are displayed in yards or meters. Additional features include a 6x optical system; single or continuous measurement (up to 8 seconds); multilayer coating on all lens and prism surfaces; long eye relief (16.7mm) which is ideal for eyeglass wearers; and a compact, ergonomic design. IPX4 Weather-resistant. Five-year manufacturer's limited warranty.