Sound balls for blind people

Sound balls in Azerbaijan, Armenia, Bulgaria, Bosnia and Herzegovina, Hungary, Greece, Georgia, Kazakhstan, Kyrgyzstan, Macedonia, Moldova, Serbia, Slovakia, Slovenia, Tajikistan, Turkmenistan, Uzbekistan, Croatia, Montenegro, can be bought in different sizes and types, for different sports of blind people. Special sound beacons in the form of bells, rattles or beepers are built into such balls. Also, balls can be made both traditionally from a shell filled with air, and from a shell with porous foam.