This Pentax SMC 67 165 mm f/2.8 Lens measures 67 mm x 3.9-inches in length and weighs 29.5 oz. This Pentax SMC 67 is intended for medium format applications such as extra large prints. With this Pentax SMC 67 medium format lens, one can easily print extremely clear 20-inch x 24-inch prints (or larger if users desire). This Pentax SMC 67 medium format lens features an aperture of f/2.8, which allows the user to take excellent images even in ordinary indoor light. Using a flash, this Pentax SMC 67 allows the user to produce other kinds of visual effects that work well in portraiture. This Pentax lens features a 165 mm focal length, which allows this medium format lens great clarity and solid depth of field in long distance shots. This Pentax lens is able to focus properly down to 0.6-inches and fits all cameras with a 67 mm filter size.