All Opti-Logic Laser Rangefinders offer line-of-sight distance measurements with  +/- 1 yard accuracy, four yard minimum ranging distance, automatic rain mode, red-dot targeting One Touch™ Instant On - Automatic Shutoff Operation and are powered by a single 9-volt alkaline battery. 

Here are brief descriptions of each laser rangefinder series:

XL Series Laser Rangefinder: measures line-of-sight distance up to 1000 yards.

XT Series Tilt-Compensated Laser Rangefinder: has two modes of operation:
  mode 1: measures line-of-sight distance
  mode 2: measures horizontal distance

LH Series Laser Rangefinder/Hypsometer: has four modes of operation:
  mode 1: measures line-of-sight distance
  mode 2: measures horizontal distance
  mode 3: measures height of a target
  mode 4: measures angle in degrees and percent grade