The Bauer Fiber Classifier is a specialized instrument for determining the weight-average fiber length of pulp fibers using the screening method in pulp and paper laboratories. It measures the proportion of fibers of different lengths in pulp and reveals the distribution of various fiber lengths in the stock. The instrument complies with GB/T 2678.1-1993, TAPPI T233 cm-95, and the Nordic SCAN M6 (10g sample, 15min water flow, 10L/min flow rate) screening methods. It features 4 screening stages, a screen chamber capacity of 10 liters, a stirrer speed of 580±1 r/min, an adjustable water flow rate of 0-20 L/min (display accuracy 0.5%R), and an adjustable screening time of 0-9999 minutes. The main body is made of 304 stainless steel with a power supply of 240W/380V and a net weight of 130 kg. The factory default screen set is for medium-long fibers (14, 28, 48, 100 mesh), with long and short fiber screen combinations also available. This instrument is an essential device for fiber morphology analysis and pulp evaluation in paper mills, research institutes, and quality inspection agencies.