These bits work with the Trinity, you probably know what that is if you are here.
There is an option for either Imperial or Metric, here is exactly what you get with each: Imperial — 9 high-speed steel bradpoint bits to joint drill for 1/4, 5/16, 3/8 inch dowels with either 1 1/2, 1 3/4, or 2 inch lengths Metric — 9 high-speed steel bra