Metal hole protectors prevent the enlarging of wooden nest boxes entrance holes by pecking or gnawing. Squirrels, woodpeckers and small mammals will damage unprotected entrance holes. For example, they attempt to enter the box for nesting or in some cases to predate on the eggs and fledglings of small birds. As a result, damaging the nest box or at worst destroying broods.

The 32mm hole protector, considered by the RSPB to be a universal size for all small hole nesting species. Such as blue tits, coal tits, marsh tits and tree sparrows as well as great tits and house sparrow. Fix using the 2 stainless steel 3mm/12mm screws included, to any wooden nest box.