Keson MP401E 4' Steel Frame Electronic Circumference Measuring WheelKeson MP401E 4' Steel Frame Electronic Circumference Measuring Wheel The MP401E is Kesons only electronic wheel with a steel frame. It is the worlds sturdiest electronic measuring wheel and the easiest and most comfortable to use. It will stand up to the harshest conditions. Features: Swan Neck Ergonomic Handle Our patent pending thumb up grip ensures less wrist strain and superior control. Reliable input system: Magnetic Sensors Dust, dirt and other