These high quality, durable bed bug interceptors create a barrier that will stop bed bugs climbing up the bed frame and onto you and your family, and also catch any on the way down. The outer rim is ridged, giving the beg bugs and bed bug nymphs the ‘purchase’ they need to climb up it. However, once over the rim they fall into the moat, which has high gloss sides that bed bugs cannot crawl out of. Inside the dish, where you place the bed or furniture legs, is rough. Again the bugs can move over this, but as they try to get out they once again fall into the trough, and are trapped.