The brachioradialis is the main recruiter, receiving great stimulus as it works as the main elbow flexor when using the pronated grip, as the biceps brachii are mechanically weak in this position.
This exercise can also be a great outlet for those who find the reverse barbell curl an uncomfortable exercise, due to stress placed on the wrist during its execution. The angle of the grip is much more wrist friendly.
Remember to keep form perfect throughout the execution of the lift to maximise tension on the target muscle, and not allow secondary muscles to aid the lift.
For hypertrophy 6-12 reps will likely yield the best results, providing optimal time under tension. This will provide adequate stimulation for sarcoplasmic hypertrophy, and acute response to anabolic hormone concentrations, compared to that of lower rep ranges.
Home Training Alternative/Limited Equipment
The brachioradialis and other elbow flexor muscles can be important in sports that require pulling and grabbing actions, such as with contact sports.