I have a 21 LT TB short box. There's lots of good options, but I went with the Lomax black urethane finished tri fold. Very happy with it so far. Really like the low profile design with no rubber gaskets on the sides.
Luke at Truck Alterations hooked me up. I purchased, Thanksgiving day and it arrived Tuesday the following week. $675 for matte shipped no tax or $710 shipped no tax for black urethane finish.