1. Composed of nylon rack and foaming materials;material-saving and uniform sealing. 2. Connected to plate with clips; suitable for cavities of different sections;precise positioning and easy mounting. 3. Keeping a clearance of 4-5mm from the cavity section of plate,without any interference to pre-treatment,electrophoresis and coating. 4. The materials are chemically stable and do not pollute the electrophoresis buffer. 5. Long shelf life