Abstract: A nesting block has a stack of panels. Adjacent panels in the stack of panels comprise a top panel and a bottom panel. Adjacent panels have a plurality of channels defined by the bottom surface of the top panel and the top surface of the bottom panel, each channel having an open end at the front edge of panels and a closed end toward the back edge of the panels. A hinge connection connects the back edges of the top panel and the bottom panel. A coupling releasably couples the top panel and the bottom panel. There is a sealing engagement between the bottom surface of the top panel and the top surface of the bottom panel and along the back edge and the opposed side edges when the top panel is coupled to the bottom panel.