Bought this in spite of the one bad review. Had bats enter the top corner of a three story house through a loose gutter. Could not manage the bat cone solution, so I cut three small holes in the interior ceiling between the ceiling joists where the rustling could be heard, and put each bag on the end of a small wire and inserted into the hole (wire in case I needed to remove it). Took about 7-10 days but the bats left. Sealed the ceiling holes and fixed the gutter. Problem solved. Only complaint is the bag material is very fragile. Would use again if I have another bat problem.