Internal filter wheel for ST-237 or ST-5C cameras. This is SBIG's previous version which uses a separate 1.25" threaded IR-blocking filter which mounts on the nosepiece of the camera (included). SBIG's current version has IR blocking built in on the R,G,and B, but not the clear.
New ones sell for $399.00
Selling this one for $265.00, postage paid in CONUS.