About 8-10 years old, SCT-type, screws onto back of scope. Fits Meade or Celestron. Filter is different than current Orion offering, says "SkyGlow UltraBlock" on it (it's the narrow-band one), surface facing scope is yellow/green/gold, surface facing diagonal is silver/blue/green. In good condition, a few specks of dust, small thread damage (see pic) but accessories still thread on ok. With hard plastic storage case. No dust covers.