Leupold Alumina Flip-Back Lens Covers are designed to cover and protect the objective lenses of Leupold riflescopes. These flip-back lens covers are made from machined aluminum, so they are both lightweight and durable, able to stand the test of time in all conditions. These Leupold Alumina Flip-Back Lens Covers come in a wide range of sizes, from 20mm to 50mm. Not only do these lens covers protect your objective lens from harsh weather, but the cover flips all the way back into a horizontal position for a low profile