Panasonic KX-TDA0190 Optional 3-Slot Base Card. The Panasonic OPB3 KX-TDA0190 is a circuitboard card compatible with KX-TDA100, KX-TDA 200, KX-TDA 600, KX-TDE100, KX-TDE 200, KX-TDE 600
Panasonic Phone Systems. Equipped with 3 connectors, the OPB3 can receive 1 or more of the following Optional Daughter cards: 4 Channel Message Card KX-TDA0191) (MSG4), 4 Port Doorphone/ Door Opener Card KX-TDA0161 (DPH4), 16 Port Echo Cancellation Card KX-TDA0166 (ECHO16), 4 Circuit Input/Output Card Contact Closure Card KX-TDA0164 (I/O). Sold as is.