The adjustable arm cuff is a medial device that you can adjust to fit your needs. In the event of a broken bone, the bones need to be set as quickly as possible. Depending on the size of the astronaut's injury, you can print one or multiple arm cuff to accommodate the need. If multiple arm cuffs are necessary they can clip together to create a longer one, and they are flexible to accommodate different widths. I would suggest that it should be made with abs plastic for the cuff and the blue part should be made of stainless steel.