SPARE-O-DOOR SPARROW TRAP FOR TRIO PURPLE MARTIN HOUSES
Keep your Purple Martins safe!
Converts any Trio house door into an effective Sparrow trap. No bait is used, the trap simply relies on the Sparrow's incessant search for nesting cavities. A red signal will tell you when the trap is occupied. A removal device is included, hence, the Sparrows can be extricated without opening the compartment.