Attach a Pre-Screen Filter to your Buon Vino Mini Jet to prolong the life of the Check Valve and maintain a much cleaner pump. A pre-filter will screen out large particles of sediment such as oak chips and/or seeds before they reach the pump. This is highly recommended for vintners using oak chips, elderberries (or other fruit bases for wines), or for using the pump to rack wine. Inlet and outlet are both 3/8" in diameter.