Bordering on the greatest thing since sliced bread, this grommet set was just what I was looking for to add the finishing touch to my husband's handmade birthday present. Instructions for use are on the back of the box and if you follow the included diagram (with parts labeled A, B, C) you will be quickly instructed to install 1/4" (bore size) bushings. The only what is missing from this set is a hammer and you will need it before you start Please note other sizes are available and although bore size is listed the bushings themselves can greatly increase the bore size which for some applications is a This is a great kit with well made tools, simple instructions and quality bushings to get good results. Buy more and recommend these kits to others.