C4S may refer to:

C4S (gene), a gene variant for encoding the protein complement component 4 Clips4Sale, adult video site SAP Cloud for Services (C4S), an application in the SAP CRM product line Menasco C-4S, an aero engine Porsche C4S, a variant of the Porsche 911 (993) Porsche C4S, a variant of the Porsche 911 (996) command, control, communications, computers, and, surveillance (C4S), a variant of command and control

See also

C4SS C4 (disambiguation) for the singular of C4s C45 (disambiguation)