The PENTAX SMC PENTAX-F FISH EYE 17-28mm F3.5-4.5 lens is a unique and specialized fisheye lens designed for Pentax cameras. With a maximum aperture of f/3.5, this lens allows for a shallow depth of field and creative perspective distortion. Made of durable aluminum and manufactured in the 1990s in Japan, this lens is a rare find for collectors and photographers looking to add a distinctive piece to their kit. The lens is compatible with Pentax cameras and features auto focus capabilities, making it a convenient and versatile option for capturing wide-angle shots with a twist.