This is a kind of quality aperture eye view trainer, whith raised scale marking design, wear resistance and with fine durability. Improving, adjustment, stereo visions, and strengthen the relationship between adjustment and collection. Suitable for the crowd of people with poor gather and disperse fusions function. Suitable for strabismus training and postoperative consolidation, increase the ranges of positive and negative fusions, and restore stereo visions with fine results. You can have a try. Raised scale marking design, wear resistance and with fine durability. Uses spectacle plate for scatter training from card's figure 1 to figure 7. Sets training use single-hole plate to train from card's figure 1 to Fiqure 12. Lengthened guide stick, not easy to bend, with fixed red fixation points. Improve amblyopia, have a fine effect on strabismus, establish the function of binocular amblyopia. Color: Black Material: plastic Package Contents: 1 set * Vision Function Slit Ruler Trainer Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.