After fluid painting for some time I was looking for a better way to filter the paint conditioner which sometimes develops skins inside the bottle after being used. This cap has a built in porous end that captures most debris to keep it out of your paint. It can be used in combination with the original cap. For best results clean after use. If it becomes clogged, soaking with isopropyl alcohol will loosen up the dried on material. An empty jug with some hot water can be used to help flush it clean.