Ben meadow’s company 5M fiberglass coated cloth tree diameter tape measure. One side of the tape measure reads normal linear measurements in centimeters,decimeters,and meters.The other side measures the diameter of the tree in Millimeters and centimeters,it does this by calibrating the tape and doing the math for you,in other words measure the tree as if your measuring circumference and that measurement equals the diameter in centimeters and millimeters. Tape is previously owned but is in excellent condition ,the metal ends are a little rusty but physically in good working condition.(price is per tape)