This Staywell 700 Series pet door is the original design. It has a lock feature which allows you to keep your pet in or out. The door is made of durable, transparent plastic, surrounded by a sturdy plastic frame. It can be easily installed into most standard windows, walls and doors. A size guide is provided below, to help choose the right door for your pet: Small - 236mm x 198mm (Cut Out Size 185mm x 158mm), Maximum Shoulder Width 147mm, Maximum Pet Weight 7kg Medium - 352mm x 294mm (Cut Out Size 281mm x 237mm), Maximum Shoulder Width 219mm, Maximum Pet Weight 18kg Large - 456mm x 386mm (Cut Out Size 370mm x 314mm), Maximum Shoulder Width 290mm, Maximum Pet Weight 45kg
