ZooziiElipse... The side drilled holes are off center to allow the finished bead to hang nicely if strung directly on beading material. The measurements are as follows: Thickness: 8mm Length: 35mm Width: 25mm This tool will accept up to a 3/32nd mandrel. Hint: This tool works well with a "chunky donut bead", a bit off center, as the "pre-press" shape. The donut should be about 1mm thinner on each side then the press is wide.