This filter is our original filter; Designed for use in a Microjet irrigation system. It is designed specifically for use in low volume, low pressure systems only.It has only one filter screen (or cartridge) available. This cartridge is made of plastic and is designed to trap any particles that would clog up a standard Microjet®. The openings in the inline filter cartridge are 1.3mm x 0.5mm which equates approximately to a 20 mesh filter screen in area of opening (0.65mm2). The smallest Microjet® is a black base which has an orifice size of 0.8mm, so this filter would work perfectly on any Microjet® System. The Emjay® Inline filter is only available with Emjay® Insert (barbed) ends in 13mm, 15mm and 20mm. These ends conform to the rest of the Emjay® range of fittings with their unique barb configuration. When using the clear barrel it is easy to see if the filter cartridge needs cleaning or is blocked.