Biofuels Biofuels include Biodiesel and Ethanol. These are fuels made from renewable resources and typically blended with refined fuels as additives. 4124A Cast iron Ambient temperature Mechanical seal options Capacities to 500 GPM 4127C 316 Stainless Steel Many sealing options Capacities to 320 GPM SG Ductile Iron Compact Installation Capacities to 190 GPM