With this adapter, you can use Viogtlander Retina DKL lens with Sony NEX NEX-3 NEX-5 Camera. It allows foucs to infinity. It may pass the infinity a bit, please use LCD to focus . With lock pin and lens release pin. Precise design. Made of Brass And Aluminum, allow install, remove and operate lens smoothly! Matte inside finsihing. avoid reflecting of light!