Yoked Prism Frame with 360° Compass and Adjustable Nose Piece
Yoked Prism Frames with elastic string are available in 2 lens sizes: 38 mm for Pediatrics, and 48 mm for adults. Comes with comfortable and soft adjustable nose piece. Comes with large thumb screw on each side so that each prism can be secured.
A 360° compass or protractor which helps to accurately position the prism base.