PETSAFE STAYWELL ALUMINIUM PET DOORS. SMALL STAYWELL ALUMINIUM PET DOOR - 600. LARGE STAYWELL ALUMINIUM PET DOOR - 640. EXTRA LARGE STAYWELL ALUMINIUM PET DOOR - 660. Fits doors 1"-2" thick, if fitting in thinner doors you will need competent DIY skills to cut the aluminium tunnel down to size.
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