These 20x20 cm filter sheets are rated at 8 micron. They provide what is considered a "rough" filtration and are great for preparing a wine for further filtration with finer sheets; usually 2 micron of smaller. Please note that all pad filters are rated 'nominal', meaning that about 90-95% of all particulate matter at the micron rating will be filtered out. There will always be a little bit of smaller material that is also filtered out, as well as some larger material that will make it through. These sheets are stamped with the code V12 so you can easily tell which sheet you are working with.
The filters can be sanitized by in-line steam, auto-claving, dry heat, hot water or chemical methods. Another method is using Saniclean solution through the pads followed by sterile water or a small amount of wine that is then discarded. After the solution is run through the pads, and the pads have softened, the filter will need to be re-tightened.
Using the Filter Sheets
Each sheet has an inlet and an outlet side, distinguished by their different textures. The inlet side is a billowy type texture, frequently called the "rough" side; and the outlet side has a crosshatch pattern and is commonly called the "smooth" side.