Flat ring is also called SMR(Super Mini Ring), It s an advanced random packing in the column tower packing. It has similar structure with cascade mini ring, There is not flanging structure at the top and bottom. It can improve the packing strength through adjust the arc of internal blade. It has reasonable flow structure, low pressure drop and high mass transfer performance. Super mini ring has two main types, which names as QH-1 and QH-2.