Northwest Instrument NSL500B 20x Transit/Level • 20x Transit/Level • Magnification: 20x, with Stadia ratio (1:100) • Transit Capability: +/- 45 • Working Range: 200ft • Leveling Accuracy: 1/4 in @ 100 ft • Minimum Focus: 3.5 ft • Objective Aperture 22 mm • Leveling Head: Three leveling screws • Includes: Carrying case, plumb bob & manual • Tripod Adaptor: 5/8 x 11 thread