I built a Maze for the BWS Gater basket with some 1 1/4" x16" angle iron. I bolted 2 lengths together with a strip of 1/8" stainless perf, with washers between the steel there is a 1/2" gap. They sit in the tray on their own weight.

After 7 hours of cooking Brisket points for burnt ends, Beef ribs and Pork Rib tips at 275* I checked to see how much had burned.

I kind of pushed the coals back towards the Guru'd vent (L/R) and added about 18 more briqs to the Right front ot the maze and 5 hours later they had just started to fire off.

Can't say exactly how much BBK I used as I emptied a couple open bags to fill the tray, but even after adding the new briqs and temps that hovered @300-318* for the remainder, I am pretty happy with the burn time.