Thanks to the extreme temperatures this winter and a wet spring and summer in the forecast, the population of blood-thirsty mosquitoes could be at an all time high this year. This three-tier American barn helps you build a healthy colony of purple martins for a mosquito free environment. The textured nesting bowls allow for quick water-drainage while the entry doors are Starling resistant. No tools for assembly. Measures 18" x 21" x 19" overall.