The 20-year-old marksman is happy to have committed his long-term future to United.
He said, "It feels good to be here and I just can't wait to get started to be honest. There were a few teams who came in but right now Sheffield United is the best option for me. Looking at the club, it is on the rise, finishing ninth last year and hopefully it can be better this season. Maybe I can add some goals, I'll work hard and try and help the team to a higher place this year.
"It was good for me (last season at Swansea). I felt I needed game time, and I scored 11 goals in 22 which was great for me. I am not going to dwell on that though, this is a new season, and I want to come in here and show what I can do, and score goals for Sheffield United.
"I am ready to come in and show everyone what I've got. It is a team that creates a lot of chances, the three at the back, overlapping, they get crosses into the box and that's my game - being in the box, finding space and one and two touch finishes. That's what I am going to try and do, and try and score goals for Sheffield United."