Rodent Excluder One Way Door - Animals Can Leave But Not Return | Ethical Rodent Control This device is designed to help a trapped squirrel or rat get out of an attic or enclosed area. First you must locate the hole they used to get in. Secure this one-way door to the hole. Place some bait at the end of the device to lure the rodent out. Place a camera or trail cam facing the exit hole to watch your uninvited guest vacate.