Keson Diameter Tape, Measures up to 23-inch Diameter Diameter tape and ruler for trees, determine the volume of a given tree Used by foresters, finds diameter of cylindrical objects Measures up to 23-inch diameter in 64ths 6 foot long x 3/8 inch wide metal tape Plastic case is approx. 1 and 7/8 inches in diameter x 5/8 inch thick