Buy Digital Adapter For Comcast -

Often sold in complete kits including a remote and power supply. It is firmware upgradeable and uses composite RCA connections.

Comcast Digital Transport Adapter DCI1011COM, Self-Installation Kit, Firmware Upgradeable, Composite Video RCA, Black | AVI | Single Core buy digital adapter for comcast

If you are replacing a specific unit for a bulk account or specialized setup, these are the most common models seen in the secondary market: Often sold in complete kits including a remote