Small Presses: The Johnson-Progress range of small presses have plate pack sizes 250, 470 and 630mm square. The plate suspension system is the sidebar version and the circular sidebars have stainless steel sleeves. The hydraulic closing device is actuated either by a hand pump or an electrically driven pump. The 250mm square filter press is particularly suited to manufacturers, research workers and universalities, who often require filter presses of relatively small capacity which are equal in performance to large commercial installations. Whilst the 470 and 630mm square filter presses have earned the confidence of manufacturers and processors over the entire spectrum of industry. Filter press sizes can be supplied with plate/frame, recessed plate packs or membrane plates.