This exercise is basketball specific because it is going to work on the skill of rebounding. It is going to work on developing strong hands and a strong back so that when the player gets their hands on a lose ball they are able to grab it, and then pull it into their body to secure it. There are a lot of times in a game where two players get their hands on a lose ball, and the player that is stronger and more aggressive usually ends up with the ball. This exercise will help to make sure that if you get your hands on the ball you have a good chance of coming away with it.
As this exercise translates over to the court and into your basketball drills and practice, it is important that you emphasize going after every rebound with both hands. Getting both hands on the ball make a world of difference, and it is a habit that needs to be ingrained into every player.