From Chums

The Neo Megafloat, our highest-rated floating eyewear retainer, comes with an increased temple size that is designed for larger frames. Filled with closed-cell foam, it’ll float up to 85 grams (3 oz.), keeping your shades off the bottom of the river. The lock-stitched ends easily slip over larger size eyewear frames. For a tighter fit, slide the retainer further down your frames.

• Jumbo-sized floating retainer for heavier glasses
• Soft, foam-filled neoprene
• Will float up to 3 oz. (85g)
• Length: 16.5″
• Weight without packaging: 0.4 oz.