Medium 12 x 6 Backyard Pollinator: approx 400 tunnels with approx 400 Leafcutter Bees. Shipped in a cardboard box which is reused to create the back and surround for the pollinator. Comes with two options for attachment to your window or other chosen location. You can order extra cocoons with your nesting box. See the options for additional 25gr, 50gr or 75gr of larvae.