This is an advanced movement to work the back while working almost every muscle of your upper body as a stabilizer.
Place two kettlebells on the floor at approximately shoulder width apart. Next, place your hands on the kettlebells and then extend your legs behind you and get up on your toes; this should be the same as a push up position. You can position your legs wider than a standard pushup position to help balance your body. Also, keep your back straight and hold your abs tight. Next, push the kettlebell that is in your left hand into the floor, like you are trying to push the floor away from you. Now, pull the other arm towards your body in a rowing position. Pull your elbow back as far as you can and then pause slightly at the top position. Slowly return the kettlebell to the starting position and then repeat with the opposite side. Continue this alternating fashion until you complete your set.
You can also repeat with one side until you complete all of your repetitions and then switch arms.