the design. were the sprue is attached to the weight it is at the bottom on one side so when you remove it it takes some of the collar off the weight and then your left with a flat spot on one side of the weight nothing wrong if your using them yourself but trying to sale them I just wouldn't in my shop and I have a hard time getting complete castings from this mold also and ive tried just about every trick I know. but this is just my opinion and everyone has one.