@f Do you have a nickel sensitivity? https://support.apple.com/en-us/HT204665
@f me too. But it began to happen a year after v5. I’d worn it for all versions but v5 did something with sensors!!! I wear it on inside of wrist to prevent that now
@f I got red bumps which later puss started oozing from - like from a burn. I used 2.5% Hydrogen Peroxide ointment on it for a couple days and it went away.
Later I got those Hydrocolloid Gel Bandages and put those over the healed skin. They allowed the sensors to still penetrate to my skin/blood yet protected me. I got tired of the extra expense and just reversed the watch on the inside of my arm. Worked ever since.
I got the 21mmx42mm size. Perfect size! Link below: