Do you have an older Frantz "SKY" Filter unit with a rubber gasket seal around the center metal tube of the filter base? If so, that gasket is no longer manufactured. It was designed to seal the bottom of the cardboard tube in the toilet paper roll so all the oil will flow down through the turns of the paper and not sneak past without getting filtered down through the cardboard tube.
You can now upgrade your older filter to match that of a current Frantz Filter with this inexpensive part which is now a permanent part of your filter. Installation is simple and requires no special tools other than a screwdriver. Instructions are included with each piece.
This part had a very sharp edge that cuts up into the turns of the paper roll outside the cardboard when the canister with new roll of TP is assembled and clamped to the filter base. This is one of two steps to solve the issue of larger cardboard tubes in the newly-manufactured toilet papers being manufactured today. The other step is one of the machined sleeves available from us. Check our catalog for information on this permanent part also.
Note: While photo shows several only one is included or required per filter.