This BC measures approximately 12" x 12" x 3.5" and is made of heavy duty, 16 gauge, 1/2" mesh wire. The other BC traps you see online are made from 19 gauge hardware cloth sold by the big box stores. I went to 16 gauge (thicker) because it adds a little extra weight to the trap, holds its shape VERY well, and can take a beating like none other if you are one that likes to toss the trap out the window as you are driving by a raptor. It is designed to be used with mice, gerbils, and sparrows. With such a low height, it keeps the raptors moving on top since they are usually less than 2" from the bait. There is nothing worse than spotting a bird you want to trap, grabbing the BC and getting it ready to put in place, only to realize your mouse / gerbil has chewed off several of the nooses. Or that your sparrow has pulled a noose inside the trap and is tangled up in it. The double ceiling on this BC prevents this from happening. I have caught Kestrels, Merlins, Cooper's hawks, Red Tailed hawks, and Ferruginous hawks with this BC. Nothing was changed about the BC except what bait was being used. It is the most versatile trap I have, and rarely fails once the bird gets on top of it. When you set this trap 30' out from a tree line or hedge row with a sparrow in it, there is no telling what you might catch.