Preliminary evaluation of the Shirley Developments, Ltd. Model F/MT III instrument for measuring micronaire Index, Maturity and Linear Density of cotton fibers indicates that the instrument has the potential speed to be considered as a candidate for inclusion in high volume instrument systems. Although the higher speed was obtained with a very slight sacrifice in precision when compared with the slower laboratory models, the test results are meaningful and significant when used as estimates of yarn dye uptake and nep content of dyed fabrics.