The Model TR1 Tru-Trac® linear measurement solution is a versatile option for tracking velocity, position, or distance over a wide variety of surfaces. An integrated encoder, measuring wheel, and spring-loaded torsion arm in one, compact unit, the Model TR1 is easy to install. The spring-loaded torsion arm offers adjustable torsion load, allowing the Model TR1 to be mounted in almost any orientation â€" even upside-down. The threaded shaft on the pivot axis is field reversible, providing mounting access from either side. With operating speeds up to 3000 feet per minute, a wide variety of configuration options â€" including multiple wheel material options â€" and a housing made from a durable, conductive composite material that minimizes static buildup, the Model TR1 Tru-Trac® is the ideal solution for countless applications.