Model-i is an optical + mechanical device which does not require electricity. Normal abnormal retinal structures are painted inside the eye. Can simulate myopic as well as hypermetropic eyes. Model-i is an ophthalmic teaching device used for practicing indirect ophthalmoscopy and retinoscopy Normal abnormal retinal structures are painted inside the eye Can simulate myopic as well as hypermetropic eyes Model-i is an optical + mechanical device which does not require electricity Instructions for Use The instructions for use and surgical technique are supplied in the form of a lea et with instructions given in diagram form where appropriate . The international symbols used on the packaging are also explained.