Phase 2 Lifters Only! Very Advanced Alternative Move!
There's a reason serious lifters rely on the barbell row for back mass and strength - it just plain works.
But for real mass building it's not for everyone because it's a difficult move to do right, especially if you use large amounts of weight, which for mass building you are going to want to.
It can be hard on the low back and keeping good form is especially important with this move, so I don't include it in my muscle building plans because of it's difficulty. But this is a move you can do instead of seated rows or lat pull downs. As a phase 2 lifter doing a combination of 2 of these 3 is excellent mass building for your back. Phase 3 lifters will do all 3, because they all work the lats at different angles. Check it out and see if you think it's right for you.