The drums are watertight cylindrical containers with variable size dimensions where the hides/skins are processed according to phase sequence of tanning process. Beam house; soaking for rehydration, liming for unhearing, deliming, degreasing. Subsequently pickling and tanning steps and finally utilized for retanning, fatliquoring and dyeing. The mechanical action on the hides, due to the rotations, maximize the skin's absorption of chemical compounds and induce the process reactions. The systems can be built using various materials: wood, stainless steel, polypropylene, etc. and fully automatized through control devices (es. rotation, temperature)