LOW VISION. Fast - Easy Bingo. Players cover numbers with sliding, see-thru red plastic shutters. Large easy to read (1/2" high)clear, readable numbers. A flick of the finger marks the numbers. Easy clearing - Brush hand over card to clear shutters. No markers or chip needed. Card size 6 5/8x7 1/2. 5-Ply; assembled with special adhesives for great durability. Sold in quantity of 20.