"Automatic Level has a top-mounted optical sight for quick reference, 360 horizontal circle and fine adjustment knobs on left and right sides with endless horizontal drive. Water and dust resistant for use in most weather conditions. Dimensions L x W x H in. 7 1/2 x 5 3/16 x 5 3/8, Single, Pair, or System Single, Magnification mm 26X, Style Automatic level, Range ft. 350, Includes Large, easy to-use focusing knob, Accuracy 1/16 in./200 ft., Ratio 100 Stadia ratio, Thread Size in. 5/8-11. Wire hung, magnetically dampened compensator Penta prism for bubble viewing 1100 stadia for distance estimation Telescope Erect Clear objective aperture 40 mm Field of view 1 30ft. Shortest focusing distance 0.315in. 0.8m Stadia addition 0 Sensitivity of bubble 8ft. 2mm Circle graduation 1 Standard deviation for 1km double-run leveling 0.689in. 1.75mm Compensator working range 15ft. Compensator setting accuracy 0.8in."