The PENTAX SMC Pentax-M 50mm f1.7 MF Lens with e-mount adapter is a standard manual focus lens designed for Pentax cameras. With a maximum aperture of f/1.7, this lens is ideal for capturing clear and sharp images with beautiful depth of field. The 50mm focal length is perfect for capturing everyday moments with a natural perspective, making it a versatile and high-quality lens for any photographer.