One of the common mistakes people make when bench pressing is fail to maintain stability through the lower half of their body. I was guilty of this before I learned the proper technique to the bench, which automatically shot my bench numbers up.
Although I'm far from calling the bench press one of my strong suits, it's crucial for me to hammer the importance of lower body stability when under the bar. The upper back-supported kettlebell press helps me get that point across off rather quickly.
Creating proper lower body tension is much easier to understand on the actual bench press thanks to the context created with this drill. By setting up in this hip thrust position, you're required to contract your glutes and anterior core hard in order to maintain proper alignment throughout the whole set.
At Iron Lion Performance we rely heavily on kettlebells in our practice, which is why I perform this with kettlebells rather than dumbbells. If you have access to dumbbells, by all means, use them.