Get my roofing partner ready for the cold.

Hello everyone! I don’t know if this fits the requirements for a post in the group but my boyfriend who is a roofer. It’s getting colder & colder every week & he will continue to work even during the snow. What can I get him to make him feel more comfortable/warm out & is useful to him in this line of work? My boyfriend is a hard worker & will work in whatever conditions so I just want him to be a bit more warmer & comfortable during work.