High efficiency cartridges Top Grade cartridge technology has been used for over 20 year and such cartridges are assembled on all SIDEROS ENGINEERING filtering units, from the movable one, ECO 2C, to the one with 24 cartridges, ECO 24 CT. Advantages: • Reduced losses of load; • Flame retardant (FLAME PROOF); • Longer life; • Less energy consumption; • Higher filtering quality; • Possibility of releasing the ait into the workplace; • Constant performances in time