Thank you Doug for providing the model numbers.
May I please get all your two cents on another related question?
Ultimately, my goal is to setup a scalable, flexible Cisco network utilizing the Cisco 2611, 2612, and Cataylst 2950 to prepare for my CCNP.
Actually, the main reason for wanting to purchase the WIC-T1 is because I have the Catalyst 2950 (layer 2) and 2612 (only one ethernet port) so if I understand it, with that setup would have problems configuring routing (eg. RIP, OSPF) between different PC's on opposite ends.
Therefore, I figured adding a serial connection on each router is the least expensive way to set it up so that I may setup such an environment.
Thank you much for your time.