The PetSafe Pet Screen Door (originally Johnson who bought it from Borwick Innovations) is one of our most popular pet door for screens. The installation is simple:  lay one frame on the floor, lay the screen over it, cut out the screen by following along the frame guide with a sharp knife, snap the other frame on top.

Although the flap dimension is large enough for a dog to about 35 lbs, because the support is only from the screen on all four sides, we recommend that it be used only with smaller and less active pets. The flap contains a locking mechanism.

PetSafe Pet Screen Door, Johnson Pet Screen Door and Borwick Innovations (the original inventor) Pet Screen Door are all the same product!

Neat idea: some people use this for passing drinks etc to the patio from the kitchen without letting bugs in.