It is composed of two truncated cones joined together by cylindrical section. A tight closing lid of the fast closing type for feeding material and a discharge butterfly valve at the other end of the unit which also renders a perfect tightness. The working capacity of the blender is 60% of total volume. The blender is recommended preferably when the product to be mixed have a similar density and particular size as well as no lumping properties. Baffles are provided in bigger unit for intense mixing.