This adapter is a black anodized metal ring that screws onto the top of a Vernonscope standard eyepiece. It replaces the eyecup and eyecup insert for times when you prefer a flat top to an eyepiece with an eyecup. It covers the threads for the eyecup insert, and has a knurled edge like the regular flat top eyepieces. The edge of the adapter extends over the edge of the eyepiece barrel by about 4mm and adds only about 2mm height. Photos coming soon.