These are rollers for making Japanese "Yaen" fishing lures, for DIY use. There are 20 pieces. They have been tested in actual fishing conditions several times. They roll very well. This is the thicker type of roller, out of the two types I am selling. The hole diameter is 1.2mm, and a 1.2mm stainless steel rod fits perfectly, allowing for smooth rotation. A 1.0mm shaft also rotates well. There are 22 colors available. Please specify your preferred number(s) after purchase. The quantity of each color can be mixed.