AEM Water / Methanol Inline Injection FilterAEM's Methanol Water Injection Filter can filter particulates as small as 40 microns. It protects the working parts of the water methanol system and the engine from particulates in the water methanol mixture when installed in line before the water methanol pump, and can be used on virtually any water methanol injection system using 1 4" OD tubing. Water Methanol Injection Inline Filter, Installs Between WMI Tank and Pump