Mixing the cotton is necessary for eliminating differences between bales and obtaining a uniform thread quality. The choice of mixer depends on the design of the blending facility, the amount of flexibility wanted from the facility, the expected production capacity, and finally on the control mechanism of the facility. In designs requiring high production capacities, and which are to be divided into several combing lines, it is necessary to use mixers with high storage capacity. In facilities with medium to low production capacities and with undivided combing lines working with constant material flow, mixer with likewise low capacity, or even small mixers placed one after the other. The chambers of the mixers are filled one after the other by a material transport motor, and equal amounts are taken out. Thus an ideal mix is obtained, both between the bales, and through time. A good mix obtained at the start of thread production has a special importance for the processes of thread production, weaving, and even finishing. Even when we don’t consider the blend disparities between bales of different origins, the differences in the maturity, color, length and thickness of the fiber cause differences in the strength, smoothness, dye absorbency, and the operation of the facility.