Strainers are designed and manufactured by Hidroflex. A Strainer is a device used to protect downstream equipment such as spray nozzles, plate heat exchangers, meters and pumps. A Strainer retains particles on the surface of its strainer element (ie on the mesh or perforated plate).
A Filter as the name suggests filters, but retains more particles inside the filter element body (ie. filter cloth or filter cartridge). Within the industry parlance filters and strainers have a similarity and its common to use these words other way around.