Big Bird Nests are made larger to accommodate birds that do not fit into conventional nests. Now with a front roll out feature. Will accommodate large birds such as Jersey Giants, Wyandottes, Brahmas, Orpingtons, Rocks and large Rhode Island Reds. The 1 tier models come in 2, 3, 4 and 5 hole sizes. Construction: galvanized side panels and perch brackets; plastic top, front & back partitions and perches. Front opening approximately 11" x 10". Sizes 2, 3, & 4 come with removable plastic nest bottoms while the 5 & 10 hole models come with metal bottoms. Nuts and bolts construction for the sizes 2, 3 & 4 hole Big Bird Nests. Need hand rivet gun for the the 5 & 10 hole Big Bird Nests. Shipped knocked down. experts recommend 1 nest box per 4 laying hens.