Used to accurately level and measure mower decks on all riding and walk behind mowers. Mower blade cutting height gauge range is 1 1/2″ to 5″. Measure tip to tip cutting edge (side to side and front to back). Measure one side cutting edge, check height on gauge then measure other side cutting edge, check height on gauge, deck is level if heights are the same. If not, deck height adjustments will need to be made.