Abstract: A blender blade assembly, blade unit, and blade assembly for mixing materials. Blender blade assembly includes a center portion that defines an axis of rotation for the assembly. The assembly includes a lower double-sided blade coupled to the center portion. The lower blade includes blade sections that extend from the center portion. In addition, the assembly includes an upper double-sided blade coupled to the center portion. The upper blade includes blade sections that extend from the center portion. The lower and upper blades are separated by a partition. One blade section of the upper blade has a top sheered portion and the other blade section has a bottom sheered portion. One blade section of the lower blade has a top sheered portion along with a blade tip pointed downwards, while the other blade section has a bottom sheered portion along with a blade tip pointed upwards.