Not an IR-cut filter!
CMOS astronomy cameras are often equipped with an IR-cut filter. This removes the infrared portion of the light. Depending on the application, this may be desirable, but it can also be an obstacle. Since such an IR-cut filter is permanently incorporated in the camera's front piece, it cannot normally be removed without destroying it. The front piece offered here does not contain an IR-cut filter, but an anti-reflective protective glass. By replacing it, you can now allow your camera to capture the entire light spectrum! (For colour cameras, this results in incorrect colour rendering which must be corrected later during processing).