I bought the factory parallax wheel from Konus, and it was terrible. It used 3 nylon screws to attach to the scope, so it liked to come off with the slightest bump from the side, and it has that ugly blue on it, so I sat down and redesigned and printed it. This one is held in place by friction and it works well. I printed in nylon 910 because that was what I had loaded on the machine. .2mm layers, 4 base and 4 top layers, and 3 perimeter layers with 30% infill. final weight was 35.5 grams (that's what Simplify 3D told me I haven't weighed it. I did print it with a brim, which I hadn't trimmed off when I took the pictures. This is slightly smaller then the factory wheel, you can see them lined up in the pictures.