Sloan Fixation Stick (also known as the Snellen Fixation Stick) was developed for us by J Snow, C.O with 10 rows of Black Letters from 20/200 to 20/20. Each of the 4 ends has different size Sloan Letters and is designed so that your fingers cover up the Optotype size listing (in red) and they are not visible to the patient. Each listing tells the examiner what is shown on the other side. One end has 20/50, a second 20/30, 20/25 and 20/20. One end of side 2 has 20/200, 20/100 and 20/80 and the other end has 20/60, 20/50 and 20/40. Jaeger sizes also shown. Use at 16 inches (40 cm). Each stick is 6 inches (15 cm) long.