Measure the harness and cavity separately
Do not substitute package width or overall size for fit.
Read where the straps sit
Use the maker’s measuring directions for the waist and thigh positions. If the chart lists only a waist figure, check the other adjustment ranges before ordering.
Check the inside cavity
An outer diameter cannot establish cavity width. Ask for the opening and usable depth, and confirm whether the quoted size is relaxed or stretched.
Check the release off the body
Read the instructions for removing the sleeve or opening the harness. Remove the product immediately if there is pain, numbness, swelling or a change in color. Do not force a tight strap or continue if it is difficult to remove.