RETRAC bubble mirrors bring safety and functionality to any heavy-duty truck, offering versatility in their application and tested quality. This round convex full-bubble mirror head features 8" diameter convex glass to provide an extra-wide-angle view of the vehicle's blind spots and the passing lane. It is constructed from rust-resistant stainless steel and features a polished finish to provide a bright, professional accent on any heavy-duty truck. This bubble mirror is also thoroughly tested to ensure long-lasting durability, undergoing both a vibration test and a 360-hour salt-spray test. It installs using a 5/16" center-mount ball stud, providing extra strength to reduce vibration, and the ball mechanism allows for simple adjustment to locate the ideal angle for each particular application (J-bracket and mounting assembly not included).