The Forest Nester is constructed from a combination of durable solid Cedar, Alder and Hazel wood. All Certified FSC timber from well managed forests. This Nest Box has several options to suit many species of nesting garden birds:- With copper hole protector on, suitable for Bluetits, Marshtits, Coaltits or Wrens. Remove the copper hole protector to reveal a larger entrance hole suitable for Great Tits, Sparrows etc. Remove whole top panel with the two screws to create an open fronted box suitable for Robins, Wagtails or Spotted Flycatchers