Description:-1. Fusional reserves - which can help in your diagnosis of binocular vision problems.2. Phorias & squints - which can improve the accuracy of your estimations & monitoring. 3. Vertical Prism Bar: With 1/2/3/4/5/6/8/10/12/14/16/18/20/25D.4. Horizontal Prism Bar: With1/2/4/6/8/10/12/14/16/18/20/25/30/35/40D.5. Box comprising a horizontal and a vertical prism bar.