The Cannon 9726-M82 removable holder has a 51mm inside diameter and fits Ubbelohde viscometers. The self-aligning holder is made of chrome-plated machined brass for corrosion resistance and includes a handle for suspending the viscometer during testing.A viscometer, also called a viscosimeter, is an instrument used to measure the friction caused by the relative motion of a Newtonian fluid and a known surface, and is usually expressed in units of poise (P), centipoise (cP), pascal seconds (Pa s), and millipascal seconds (mPa s). Viscometers have several forms, including but not limited to falling ball, rotational, vibrating, capillary, funnel, and bubble. A falling ball viscometer measures the time it takes for a ball of known diameter and density to fall through fluid in a cylinder of known diameter. A rotational viscometer measures the force required to stir a fluid. A vibrating viscometer measures the power input necessary to keep the oscillator vibrating at constant amplitude while immersed in a fluid. A capillary viscometer has a narrow-bore vertical section with two printed marks that measure time required for a known volume of fluid to fall a known distance. A funnel viscometer, such as a Ford, Zahn, or Shell cup, measures the time it takes a known volume of fluid to flow from the base of a cone through a short tube. A bubble viscometer measures the time required for an air bubble to rise through a fluid. Viscosity measurements are used in laboratories, research and development, process control, and plant quality control applications. Some viscometers are manufactured to meet industry or governmental standards, including Ingress Protection (IP), National Institute of Standards and Technology (NIST), International Standards Organization (ISO), and ASTM International (formerly American Society for Testing and Materials)CANNON Instrument Company manufacturers viscosity measurement products, including custom viscosity/density standards, and provides testing and certification of samples. The company, founded in 1938 and located in State College, PA, is a National Institute of Standards and Technology delegate for provision of U.S. national standards for viscosity measurement.