They're in my unfinished basement. Culligan (on Wolverine's dime) handles the service, had one replacement in almost 2 years. They just disconnect,install refurbished units, and bring my old ones back to contain the chemical waste and repack with fresh carbon.

Typically the filter is a tube with connectors on end. Most soda fountain machines have a pair of inline 36" x 6" filter for activated charcoal and water softeners mounted on the wall somewhere.