A foam ball fitted over the microphone of a sound level meter to reduce the effects of wind induced noise on the readings being carried out. Windscreens are often manufactured from open cell design foams to allow free passage to the sounds of interest without unduly affecting the frequency response of the system beyond acceptable limits. Foam windscreens should always be used when performing outdoor measurements but will not be effective if allowed to become waterlogged or when used in high wind speeds in excess about 30 f/s (or 10 m/s, ~ 20 mph).