The Inspire 2 "Starter Kit" was designed to give you the essentials you need to get off the ground. The kit includes a Tiffen Circular Polarizer, which is perfect for removing glare off of metallic surfaces such as water or glass, as well as adding a pop of contrast to those partly cloudy days. Also included is a Tiffen NATural ND 1.5 (5 Stop) Filter. The NATual ND technology is the latest advancement in Neutral Density technology from Tiffen. The NATual ND was designed for Motion Picture and Television camera sensors and works flawlessly with the Zenmuse sensor.