Keep your optics protected with the Flip-Open™ Objective Lens Cover. With a fast, Flip-Open design and silent spring hinges, you can quickly utilize your scope without spooking game. In addition, the Butler Creek® Flip-Open Objective Lens Cover is watertight and airtight. FEATURES: Fast, Flip-Open™ design Silent spring hinges Watertight, custom fit friction mounts anchor to scope Airtight semi-O-ring keeps out dust and moisture Tested to –40°F Ambidextrous Weighs less than an ounce Also made for spotting scopes SPECS: Size 29: 48.7mm Size 31: 51.7mm Size 33: 51.9mm Size 40: 57.2mm Size 44: 59.9mm