I purchased this about 7 years ago when looking to buy land in the mountains. It minutes I would know exactly how many feet the lot was dropping over a given distance. I also used it while building a deck. I is precise to 1/8" and has many uses. You can measure up to 200' and a drop of 20'. It is in "like new condition," has been barely used but is in need of service. Zip services them for 0. It will need to be charged/fluid refilled at which time they update any software.The Compulevel product was dropped by Stanley and picked up by Zip. They are the same unit. The average price for this unit is 0 to ,000. There is a unit with less line that goes for less.