Either or. I'll pick up my next post in the morning, but you can add some stuff during the night too if you want! And wow, that's super warm! It usually doesn't get hotter than like 85 degrees where I live (~30C) Even that is too much for me to be going out on walks or hikes. I prefer when it's under 80 (like 25C maximum) A lot of people in the Phoenix area hike with their dogs when it's over 100 degrees (~40C) and I think I heard laws have been passed to prohibit it because it's so dangerous for them