Hammer Curls and how to do them.
 

A hammer curl is a biceps curl variant that targets muscles in the upper and lower arm. Although this exercise is typically commonly done with a dumbbell, it may also be done using cables or bands. The hammer curl is an excellent upper-body strength exercise. Also known as: biceps curl with neutral grip.


https://www.youtube.com/watch?v=icXWnjNoBBw