Well it certainly appears to be a Studio Projects B-1 with a pad and a bass cut switch, which leaves only 4 possibilities:
1. It's some kind of early production model that had those features, since discontinued.
2. It's fresh out of the factory, and they've decided to add those features (which would be cool)
3. The mic is modded, adding those features (which might or might not be cool)
4. It is a fake (which would not be cool)
I think only Alan Hyatt can answer this one. I assure you my B-1 has no pad, and no bass cut switches, which is too bad.
Anyway, seeing as how you obviously have those features, here's what they are for:
A pad, also known as an attenuator, decreases the mic's output by a set amount. This is used when recording very loud sources, such as cranked up amps and kick drum, which can overload the mic or other components in the signal chain, causing nasty distortion called clipping.
Bass cut, also known as a high pass filter, is used to avoid picking up low frequency rumble, such as footsteps, and can be used to decrease bleed from low frequency sources such as kick drum when you are trying to record snare. It can also be used to decrease low frequency boom when recording
acoustic guitar or similar instruments.
Alan Hyatt, who is an occasional poster on this board, owns PMI, the parent company of Studio Projects, and will be happy to answer your email. I'm sure he can explain why this mic has those features. They are perfectly good features, but I've never seen them on a B-1.
Here's a picture right from SP's web site-
http://www.studioprojects.com/b1.html
There ain't no switches on that mic, so how come you have them? Beats me.-Richie