Welding filter bag with plastic ring for liquid The plastic ring is made of high quality engineering plastic, which is of high physical performance and chemical causticity-proof ability. With the special treatment, it can be equipped in almost bag filters in the market. As a part of the filter bag, the handle is higher Than the filtrate level, which makes high efficiency for replacement. The filter material is polyester or pp, and filtration precision is from 0.5 micron to 300 micron.