This is a hood for a canon 16-55mm DSLR zoom lens with a diameter of 58mm for solar eclipses. You have to apply the AstroSolar film yourselfUse double sided sticky tape on the (square) top of the "solar-lenscap-bottom.stl" thing. stick the BAADER AstroSolar Safety film on top of the double sided sticky tape. and snap on the "solar-lenscap-top" Then hang it inside the ring of your lens. It should fit snugly and not immediatly fall out. IF this is not the case. Consider using double sided sticky tape on the edges of the ring to keep it in place. I wanted to share it because of the solar eclipse next week I'm also working on an iphone 6 holder for this type of foil. Source for the film: http://www.robtics.nl/product_info.php?products_id=1339