Distributors and collectors are combined and integrated into a single device, integrated internal. Integrated internals for packed columns can save column height, reduce cost, improve schedule, avoid leakage, and offer better performance. The coefficient of variance of liquid distribution can be controlled within 2% for columns up to 5 meters. The other advantages of integrated internals include well mixed liquid from the bed above and low vapor pressure drop. The integrated internals enable the shop installation of packing and internals into the column before the shipment to the field and avoid any installation works at the field.