Originally Posted by diver 1
I'm another bloc fan based on getting a fairly decent pair for £20 and going through at least 2 pairs a year. Good for the mountain biking too. The bloc glasses are supposed to be fairly reputable and are UV400 rated and polarised but are they going to cause me harm in years to come?
UV400 is the standard for protection. The main issue is dark lenses that do not include UV filters, because when worn, pupils will naturally dilate to allow more visible light in, and at the same time allow UV to penetrate.
Another consideration is periphery exposure to UV - it isn't only apparent at the front of the frame, so close fitting wrap frames offer better protection.