just in case anyone is interested in how it works, the yellow top has a "funnel" that goes down a couple inches. The flies go in, down the funnel and into the main part of the trap. Since the funnel narrows to a very small opening, and flies crawl the sides to get out, they can't get back out of the trap. They get some bait on their wings and fall into the water poison and thats it. low tech, but works great.

Black Flag Fly Motel Outdoor Trap

by Blackflag

Product Features

Best Use: Keep flies away from family activity in the backyard or where people are enjoying the outdoors.
Benefits: Starts working in minutes! The fastest, strongest lure available! Attracts all major species so it's the only product you'll need. Like all Motel® products, it's pesticide-free.

Product Description

Use Tips: Place 5-6 ft. above ground (on tree, fence, pole, etc.) in areas where flies congregate around the home. Do not hang near human activity. For best results, use 2-3 Motels spaced 10-20 ft. Do not use indoors. Wash hands immediately with soap and water if you contact lure attractant. To discard, push down to close vane and place in closed garbage container. If desired, the Fly Motel Outdoor Trap can be re-used after emptied by using Fly Motel Outdoor Trap Replacement Lures