Alumacart Aluminum Wagon Walls (Wagon Not Included) NewRemovable wagon walls are available as an optional accessory for all Alumacart wagon styles. Walls stand 8. 5 tall, fabricated using 4 x 1 aluminum channel for horizontal walls and 1 x 1 8 square aluminum tubing for wall uprights. Walls slide into ten aluminum receivers (1 1 4 square tubes) that are bolted to the bed of the wagons with all stainless steel hardware. Can be removed at any time, each side can be independently removed also.