Your large dog can easily let itself out with the 2-way dog flap. Set it to unlocked to give your pet more freedom, or to locked if you don't want your pet to use the door. This cat flap from PetSafe can be installed in just three simple steps. It is also suitable for wooden doors, PVC, uPVC, and metal doors, as well as brick walls. The insulating frame attached in front of the flap and the magnetic closure at the bottom make this cat door windproof and secure with its two locking modes. The dimensions of the PetSafe freedom door are 45.6 x 38.6 cm; maximum shoulder width is 29 cm. It is suitable for large dogs weighing up to 45 kg. With this pet flap, your pet has access to selected areas and can move freely within them.