Interior dimensions are 22" tall, 16" across the bottom, 8" front to back and 8" tall "toe." Inspection door is on top of the "toe." Entrance hole is 3.5" Especially suited for Rock Pebblers, rosellas, and other Australian parakeets.
Left or Right mounted boxes are determined by which side of your habitat the box will be mounted if you are standing in front, facing the habitat.