Monofilament line at 4.00mm spacing provides reference to the size of the optic disc. Estimate the size of inflammatory/non inflammatory retinal lesions. Grid spacing aides in estimating the size of ocular tumors. Easily estimates the amount of disk edema. Ideal for ROP. Designed to fit anterior side of Ocular 28D Indirect Lenses*. The Ocular 28D Indirect Lenses are sold separately (see related products). *Lens design with diamond knurl pattern only
