Ring filter disc, also called ring wire mesh filter disc or annulus/annular filter disc, is made of single or multi-layer woven mesh in plain, twill or dutch weave type and it has an ring shape. Ring filter disc can be made from different kinds of materials such as stainless steel, aluminium, copper or brass. Because of its high porosity, permeability and anti-acid, ring filter disc is widely applied for gas, liquid filtration as well as other medium separation in pharmaceutical, petrochemical and food industry.