A Natural Way of Combating Insect PopulationsConsuming over 600 insects per hour, bats are welcome summer visitors to those looking to control local mosquito populations. This full-sized, single cell bat house kit (once assembled) will house approximately 30 bats. This design represents over 10 years of research and successful bat house building experience. Complete assembly instructions are included. All holes are pre-drilled.Measures 18" x 12".