The PetSafe Wall Entry Extension Tunnel is designed for walls more than 7 1/4″ thick.
Small wall entry doors can be extended up to 10 3/4″ thick, while medium and large can be extended up to 12″.
Compatible with the following PetSafe Pet Doors: Plastic Wall Entry Door (model # ZPA00-16203);
Aluminum Wall Entry Door (model # PPA11-10917).
Extends Wall Entry Doors from 7 1/4 in to 12 in thick.
Tunnel can be cut shorter to accommodate walls 7 1/4 in to 8 1/4 in thick.
Package dimensions: 33.07 in L X 6.57 in W X 1.81 in H.