Genuine Sigma CA512-82 Lens Cap Adapter Ring for 12-24mm f/4.5-5.6 DG HSM II, 12-24mm f/4.5-5.6 EX DG HSM or 15-30mm f/3.5-4.5 EX DG Lenses. This adapter is in excellent condition showing less than normal signs of use. Absolutely no cracks, splits or drop marks. Threads are perfect. Inner felt is excellent. No bends or dents in metal. Item is fully functional. See photos, what you see is what you get.