The black, 19/20mm Baseball Felt-Covered Windscreen from Rycote is designed to fit over a shotgun or similarly shaped microphone and greatly reduce unwanted 'swooshes' during fast swings and other rapid boom-pole movements. It is lightweight and offers increased performance over conventional foam windscreens.
The Baseball is built with open-cell foam and covered in a felt material. It can be used for fast/deep booming and plosive reduction. Additionally, it helps to protect your mic.