Thank you for viewing this item. This is a Canon Extender (teleconverter) 1.4x II. It reduces the aperture by one stop, but it's a conversion lens that increases the focal length by 1.4 times. For example, when used with a 70-200mm/F2.8 lens, it can be used as a 100-280mm/F4 lens. Please check compatibility with your equipment yourself. In my amateur opinion, there is almost no dust or debris in the optical system, and it's in like-new condition. Also, the condition of the weather-resistant seals, which are an indicator of deterioration, is good. (Please judge from the product images for details) The included accessories are the main body and front/rear caps only. If you have any questions or requests for additional photos, please feel free to comment. #Canon #CANON #Extender #Teleconverter #Telecon 1.4x x1.4 EF1.4 ef1.4 #Lens #Telephoto