Sorry I didn't think of you, will call on you for cold related problems in the future. Thank you on behalf of OP.That is mild frostbite, I am pretty sure. I wouldn’t handle the comb or do anything. Frostbite can take a few days to know how bad it might be. I have had some mild cases look normal later, and since his comb is red above the line, he may be okay. Comb tips with bad frostbite usually become rounded off after several weeks and heal on their own. Many of us in freezing winter climates see this in January and Feb.