Attract beautiful, musical bluebirds to your yard while dissuading sparrow invaders with this Coveside Sparrow-Resistant Eastern Bluebird House. The innovative design of this nest box effectively deters sparrows from roosting, while providing bluebirds a great housing option. Research from the University of Kentucky found that bluebirds will readily use a slot entry, while sparrows prefer a round hole. The 4" long and 1.25" high, rectangular entry on this shelter perfectly meets these needs, and a generous, overhanging roof protects the interior from precipitation. Place the included, 1.5" thick, pine block at the base of the home to decrease its depth, as this same research indicates that bluebirds will still roost, while sparrows prefer a deeper nest. The open corners below the roof keep this home ventilated and aid in regulating its internal temperature, bolstered by the 0.75" thick, all pine construction. Pull the front panel of this home upward for nest checks and to add the wooden block for less depth if needed. A metal latch keeps the home securely closed, and the rough interior of the item helps nestlings grip it and climb out. The pine panels create this well-researched nest box, and the unit will offer many seasons of service to select songbirds. Use the attached, back hanger to place the home against a post or wall, or pole mount it with a mounting bracket (not included). Discourage sparrows from overtaking your bluebird trail thanks to this Sparrow-Resistant Eastern Bluebird House. Made in the USA.