The Basic Series boxes are made of premium quality Fir and assemble using finger joints. These are the same joints you see in the construction of old chests and wood boxes. It is very strong but a lot of end grain is exposed to the elements so you need to keep your boxes painted to prevent them from rotting. To assemble this joint you just slip the notches together and nail them after checking them with a square. Hand grips are routed into all four side of the boxes.