Carson Optical Paracord Eyewear Retainers Blue/Black/White. The EX-50 Paracord Glasses Retainers feature a universal fit and adjustable knot for tightening on your glasses. They are made of braided nylon. Great for hiking biking outdoor adventures and everyday use Specifications for Carson Optical Paracord Glasses Retainers: Manufacturer: Carson Size: 8 in Age Group: Adults Gender: Unisex Fabric/Material: Braided Nylon Type: Retainers Weight: 0.01 lb Quantity: 1 Features of Carson Optical Paracord Glasses Retainers Universal fit and adjustable knot for tightening on your glasses Package Contents: Carson Optical Paracord Glasses Retainers Carson Optical EX-50BUB: Paracord Glasses Retainers Blue/Black/White