CST/berger 32-EZ1 4-Inch Single Measuring Wheel Wide, Precession Molded Wheels. Firm, Stable Grip on Smooth or Hard Surfaces 5-Digit Counters. Free-spinning wheel for easy rolling Molded Plastic Measuring Counter. Records to 10,000-Feet or 10,000 meters with convenient push-button reset Safety color. Impact Resistant Counter that adds forwards and the subtracts when rolled backwards 2 Different Handle Types: Easy to See, Easy to Locate