I'd have to see more, but his back is straight as an arrow, there's no belly and his snout (no good pics) would say 3.5.
3.5/4.5 is a tough spot, but it's best to err on the side of caution. If he's 3.5, may wind up shot on a neighboring lease. If he's 3.5 and someone on your lease decides he's a shooter, he's 100% dead if they shoot straight. That's the tough part of letting deer walk. Guy the next lease over might decide to shoot...you can only control what you can control. If he's still alive and on camera after the season's over, that's a win for you.
This post was edited on 12/9 2:08 AM by Jeff J.