The Sparrow Trap Door with Audio comes complete with our integrated audio sparrow call module. A call will improve your catch rate and increase sparrow interest in the trap door. Male and female birds cannot resist the call and come running – you will be amazed at how fast it works. The module adheres directly to the rear of the feeding platform. Penetrations in the rear baffle of the trap amplify and direct the sound to draw birds into the bait area for capture. The battery powered audio call module is loaded with multiple call programs including constant call, time delay call, intermittent call, loud and soft call, etc. In sanitary and food safety applications where baited traps are not allowed the trap can be used with audio call alone. Batteries included. Battery runtime = approximately 7 days. Or use with optional power adapter and cable TT-SP27.