just the one 421. but it's nice blended with 57. If we're getting into slightly more pricy mics, EV RE20 and Beyer T88 also do great job for bass cab micing.
I actually find my favourite bass cab micing sound is achieved by placing the mic about a foot away from the cab. As I have a vertical 2x12 cab, I also found having the mic pointing at the upper speaker sounded better. But all of that is my experience and your preferences, tone requirements may be completely different!
I'll say one thing about the D112 though. I thought about buying one, but ultimately went with other mics because I felt the 112 was too pre-eq'd (can be a good thing for others), and that 421, RE20 and T88 are all more versatile. 421 is a killer instrument mic and T88/RE20 are fantastic vocal mics.
All of that is my opinion and could be complete rubbish