Sierra Instruments introduces the new Cal=Trak™ XL Primary Standard Gas Flow Calibrator for high flows up to 500 slpm. Ideal for calibration of gas measuring instruments including mass flow meters and controllers, Cal=Trak™ XL offers class-leading accuracy of +/- 0.25% of reading. The dimensionally-based primary accuracy of the Cal=Trak™ XL is superior to pressure-based secondary methods and is backed by a rigorous uncertainty analysis. The Cal=Trak™ XL is a primary standard piston prover that operates with the press of a button--assuring end-users the ultimate in calibration accuracy, convenience, ease-of-use and productivity. At 24"W x 30"H x 12"D, Cal=Trak™ XL fits on any laboratory bench replacing large bell provers with one simple, integrated package. It can be used in the manufacture, inspection, validation and recalibration of mass flow controllers, flow meters and many other varieties of flow equipment with flow rates too high for common primary standard devices.