The old Nautilus pullover machine might be the best overall lat movement that exists.
But if you don't have access to antique strength training equipment, then the dumbbell pullover is a solid alternative. Problem is, once the dumbbell crosses over your face there's basically zero resistance in the movement. Here's how to solve that problem.
Adding a band increases the resistance through the movement. You'll get a similar affect as you would with the classic pullover machine.