APE- Ribbon Blender / Mixers are a specific type of powder blenders that consist of 2 parts mounted on a central shaft . The mixing medium often consists of inner and outer helical ribbons that are designed to move material both inwards and outwards. The external helical ribbons pull product from the sides of the mixer into the middle and the internal ribbons push the product back to the sides. The back-and-forth folding motion of the materials to be blended creates a convective mixing pattern.