Immunity boosterNatural source of electrolytesNatural source of electrolytes Additional mineral block for small birds ​ ​Contains a balanced blend of minerals and other valuable nutrients to boost your birds natural resistance. The block also gives the birds something to do. It's a natural source of calcium which has a positive influence on the bones. Immunity boosterNatural source of electrolytesNatural source of electrolytes Additional mineral block for small birds ​ ​Contains a balanced blend of minerals and other valuable nutrients to boost your birds natural resistance. The block also gives the birds something to do. It's a natural source of calcium which has a positive influence on the bones.