Manito is the first and the only one in the industry worldwide to introduce refraction free flat surface 99% UV resistant optical sheet on the stroller covers to protect baby s vision. Clear flat surface optical windows on three side screens 99% of UV rays and provides clear vision without any optical refraction and also aids vision development on infants. (Optical distortion or refraction can be found on vinyl covers which doesn t stay flat therefore it may cause dizziness and tiredness in the eyes during the early stages of development)