This is the AT4053b-EL hypercardioid capsule, for use with the AT4900B-48 body. Listing is for the capsule ONLY. In other words, if you have an AT4051b or AT4049b, you can swap this capsule on and turn it into an AT4053b. The 4053b has a tighter pattern than the 4051b and is excellent as a boom mic for dialog (or podcasting!) and other spot duties where you need more isolation. It has somewhat flatter frequency response than the 4051b (less treble lift), and of course marginally more proximity effect. Sounds great on acoustic guitar, drums, vocals etc. Anything where you need tight pattern and clean, realistic sound. Even works well for podcasting. Comes with a case and spare windscreen.
I also have an AT4051b mic (body + cardioid capsule) for sale. If you'd like to buy that mic and this capsule together, message me for a combo price.