The 70-180mm F/2.8 features a compact and lightweight design with a 67mm filter diameter, the same as Tamron's highly esteemed 17-28mm F/2.8 (Model A046) and the 28-75mm F/2.8 (Model A036). The optical construction includes several special lens elements that contribute to the lens's overall superb imaging performance. Its very short 33.5" MOD (Minimum Object Distance) expands overall versatility. The lens utilizes Tamron's newly developed VXD (Voice-coil eXtreme-torque Drive) linear motor focus mechanism that produces an autofocus drive that's quieter and quicker than ever before. Additionally, a floating system is used to achieve excellent optical performance at all shooting distances. By simultaneously operating two VXD units via electronic control, the system produces clear and sharp images of all objects near and far. Other features that support a great shooting experience include Moisture-Resistant Construction for added weather protection and Fluorine Coating for easy maintenance. In addition, the 70-180mm F/2.8 is fully compatible with various camera-specific features including Fast Hybrid AF and Eye AF. Developed under the concept of "making large aperture zoom lenses user-friendly," the 70-180mm F/2.8 provides users with complete portrait-to-telephoto lens range coverage. This new model joins the 17-28mm F/2.8 Di III RXD and the 28-75mm F/2.8 Di III RXD to complete Tamron's fast zoom lens trinity for full-frame mirrorless cameras.