May act as a scaffolding protein within caveolar membranes, functionally participating in formation of caveolae or caveolae-like vesicles. May be involved in epidermal cell adhesion and epidermal structure and function. Heterooligomeric complex of flotillin-1 and flotillin-2 and caveolin-1 and caveolin-2. Interacts with ECPAS (By similarity). Membrane-associated protein of caveolae. Expressed in many tissues, including suprabasal epidermis, hair follicles, heart, lung, thymus, spleen, liver, kidney and brain. Not expressed in skeletal muscle. ZDHHC5-catalyzed palmitoylation may be required for the formation of higher-order complexes and for neurite outgrowth in cultured neural stem cells. Belongs to the band 7/mec-2 family. Flotillin subfamily.