The 1.55"" replacement bingo balls are made from polypropylene, printed with large black letters and numbers, 1.5"" in diameter, lightweight and smooth, with no sharp edges. Before purchasing, please make sure that 1.55"" balls are the size you need for your bingo game. This set includes 75 balls and is designed exclusively with manual large bingo cages, such as those with a diameter of 13"". These bingo balls are not suitable for small bingo cages and will not work with cages 8"" tall or less. It is ideal for parties, raffle drums, bingo nights, and more.