I found this while cleaning out my grandfather's house, and as I'm a complete novice with cameras, I don't know the details. Since the details are unknown, I'm selling it as junk to anyone who's interested. The following is AI-generated text: Mount adapter for attaching Hasselblad lenses to Nikon cameras. - Brand: Kenko - Model Name: Mount Adapter - Compatible Lenses: Hasselblad lens - Compatible Cameras: Nikon - Included Accessories: Instruction manual Thank you for looking.