The Extech 461891-NIST Contact Tachometer is a reliable tool for measuring the contact surface speeds of rotating objects. This tachometer is designed to provide accurate and convenient measurements, making it an essential device for various applications.The Extech 461891 features surface wheels that allow you to measure the contact surface speeds of rotating objects with a range of 10 to 9,999 rpm. By placing the surface wheel in contact with the rotating object, you can easily obtain precise speed measurements.Equipped with a memory button, the Extech 461891 enables you to hold the last reading and recall the minimum and maximum readings. This convenient feature allows you to easily track and monitor speed variations over time.Designed with user convenience in mind, the Extech 461891 is compact and easy to use. Its straightforward interface ensures that you can operate the device with ease, providing you with quick and accurate speed measurements.Whether you need to measure the speed of rotating machinery, engines, or other equipment, the Extech 461891 Contact Tachometer is a reliable and efficient choice. Its surface wheels and memory function make it suitable for a wide range of applications, including industrial maintenance, automotive, and manufacturing industries. It includes NIST Certification.