The PolarPro Underwater Filter 3-pack includes all the essential filters you need for underwater filming. Included is a Red Filter for filming in blue and tropical waters, a Magenta Filter for filming in green waters, and a snorkel Filter for filming above water. The red and magenta filters are essential for scuba diving or snorkeling under 12 feet (4 meters) to properly record colors. The reason being, below 12 feet the wavelength of red light disappears. The GoPro camera has an automatic white balance and thinks the wavelength red is still present. This causes the GoPro to record colors, which are oversaturated with blue or green, leaving out all the vibrant tropical colors. By placing a red or magenta filter in front of the camera, you are filtering out the excess blues and greens, leaving behind vivid underwater colors. The snorkel filter is designed for filming at shallow depths from 2 to 15 feet deep. These Filters will only fit the GoPro Hero4 and Hero3+ Standard 40m Housing. Before your next dive trip pick up this three pack and capture the best possible underwater videos.