These do not have a heavy frame, in fact they have no frame at all to block your peripheral vision.  They do a good job of keeping the sunlight from leaking in the sides of my prescription glasses and bothering my eyes.  The nose bridge was a little rough, hence the four stars instead of five.  I fixed it by applying a pair of those skinny clear silicone peel 'n stick nose pads.  UPDATE:  3/16/16.  They break incredibly easily.  I can no longer recommend this product.