For those who like to build their own bat box don’t use galvanised mesh as a landing pad. After 10 years of solid use the bats urine completely rust the mesh. Including steel staples. The metal turns into barbed wire projections causing the bats to abandon the box. I now use stainless steel mesh.

Link for the mesh: https://www.bunnings.com.au/whites-190mm-x-4m-stainless-steel-ember-mesh-ultra_p3041135