RSPB exclusive Simple to install, inspect & clean, Schwegler nextboxes are famous for their durability. Schwegler have been making nest boxes for birds, bats & insects for over 50 years. These nestboxes, in colours exclusive to the RSPB, will last at least 20-25 years & are readily adopted by garden birds. They are made from a patented wood-concrete material consisting of 75% wood, which provides insulation & aids ventilation. Comes with easy-hang hook, & a forestry approved aluminium nail is included. Backed by an incredible 25 year guarantee! The 32 mm entry hole nest box may attract tits, sparrows, redstarts & nuthatches.