This Vivitar Series 1 lens using a Pentax mount, and this 100-400 mm lens offers a variety of shots from a single point. The maximum aperture range on the Vivitar lens is f/4.5 to f/6.7, while the minimum aperture is f/32, allowing the user to find the perfect exposure for the desired shot. The angular range is 6.4 degrees to 24 degrees, allowing a variety of subject-focused shots. The autofocus provides fast, accurate focusing to capture moving subjects. The Vivitar Series 1 has an aspherical lens that works to improve color balance, distortion reduction, and illumination from edge to edge. The on this Vivitar lens offers a one-touch zoom control to help the user achieve the desired image. This 100-400 mm lens has a minimum focus distance of 6.5 feet, allowing the photographer to shoot wildlife, events, landscapes, and group photos. It accepts a 67 mm filter. The Vivitar Series 1 is 6.3 inches long and 2.9 inches in diameter. This durable lens weighs 25.9 ounces.