The ARO 1001 Series 3 pc. Filter/Regulator/Lubricator Combination Unit sets the standard for air flow performance. These FRL solutions can keep your facility online and your equipment in shape because we combined best-in-class air flow performance with the flexibility to work in any environment. Filters, regulators, lubricators and piggybacks can be combined together to form combinations. They are typically strung together in the F+R+L arrangement (three-piece combo) and F/R+L (two-piece combo) arrangement, although other configurations are also used depending on application needs. ARO-Flo combination FRLs are easily assembled using modular spacer kits.