If you want to maximize your Range of Motion (ROM) in a pulling movement, Lat Rows or Lat Pulldowns for example, I think that nothing beats a long chain. The stuff you buy in the stores or online is usually short and the angles are locked, so it won't allow your natural body mechanics and minor irregularities of joint angles to fully express themselves during the movement. In plain English, you can hurt yourself.
First of all, I picked up the following items at Lowe's (Home Depot or whatever is fine):
1 10' 2/0 chain
3 1/4 screw links
1 7/16 snap link
At Sports Authority I got a pair of single D-Handles. All together, the total was pretty close to $30, about the price of a standard Double-D Welded Handle.
I didn't need a whole 10' of chain, but I have some other stuff I'm working on, and I had the good fortune to already have a Bolt Cutter, but you could get bulk chain and cut it at the hardware store. I counted out links and cut two 2' sections.
I put two screw links in the two D-Handles, and connected each to one end of one piece of chain.
Then connected the two pieces of chain at the other end with the snaplink. I added the last screw link in to adjust the length when I use it. Below you can see how I connected the trailing extra chain to one side with the screw link to keep it from flopping around in motion.
For my "test" I put it on my Lat Tower in my Power Rack.
I did some Low Lat Rows, showing here how the fuller range of motion really hits the Rhomboids:
For only about $30 and about 15 minutes of work, I built my own Long Chain Twin D-Handle Accessory Attachment. Well worth the effort and money and time.
Video Demonstrates Proper Use as Low Row on Lat Tower.