PK-EOS Lens Mount Adapter Ring for Pentax Phoenix PK Lens to Canon EF EOS Camera Features: There is no ROM connection on the ring; diaphragm control of the lens must be set manually. This adapter allows you to use manual focus lenses designed for Pentax K mount. Constructed with solid and durable materials; high-precision machining with a smooth copper interface to prevent scratching between the lens and camera. Easy to install and operate; provides secure fit and smooth attachment, helping protect both camera and lens. Specification: Model: PK-EOS Type: Adapter Ring Compatible Lens: All manual PK mount lenses (for Pentax, Phoenix, Ricoh, Vivitar, etc.) Compatible Camera: Canon EOS DSLR cameras, including select full-frame and film models Material: Metal Dimensions: 7 x 7 x 1 cm (approximately 2.76 x 2.76 x 0.39 inches) Color: Silver Quantity: 1 piece Note: Conversion: 1 cm = 10 mm = 0.39 inch No retail packaging included. Allow 1-3 mm error due to manual measurement; please confirm you are comfortable with this before purchasing. Due to differences in monitor displays, the actual color of the item may vary slightly from the picture. Package includes: 1 x Lens Mount Adapter (other accessories shown in images are not included)