Wording question on resume

I worked this summer doing 2 jobs, one being IB internship and the other being Fedex. I worked the night shift at Fedex to be able to make money in turn to be able to do the unpaid IB internship. How could I word Fedex in my resume? I didn't have it on my resume but multiple people told me to put it on because it shows determination. I worked 2am-10am and then did my internship 10-5pm. I would typically sort packages on a conveyor belt 6 different ways with up to 20,000 packages coming down my belt in a given shift.