Set of 22 square prisms in powers from 1/2 to 50 with separate red lens.
 
Power: 1/2△, 1△, 2△, 3△, 4△, 5△, 6△, 7△, 8△, 9△, 10△, 12△, 14△, 16△, 18△, 20△, 25△, 30△, 35△, 40△, 45△, 50△