Synthrotek's Eurorack Case Brackets are designed to fit flush inside your custom Eurorack case, avoiding unsightly holes on the outside of the case. Includes a pair of 3U brackets, Four rail-mounting screws, Four case-mounting wood screws, 3mm slide nuts (module screws not included) and 84HP Eurorack rails. Measurement info: The brackets are 0.122" (just shy of 1/8") thick, 5.15" high and 1" deep. Each HP is 0.2 inches wide. You can calculate the total width you will need before you receive your package. If for example you choose 84HP rails, the width will be 16.8" (for the rails) plus 0.25" (for the brackets), 17.05" total.