Hitting up a back day!
Cable Lat Pull-down: the purpose of this exercise is to isolate the lat and build the width through burn-out. The key here is keeping your elbows in line with your lat and your chest puffed out in order to keep you from kinking your spine. Also, be sure to let the weight down as far as possible in order to stretch the lat, thus circulating blood throughout the muscle. Give them a try!