Patio Pacific Thermo Panel, Quick Panel, Electronic Panels and
  Panel Cat Door for Sliding Glass & Screen Doors

Installation Instructions 
Inspect the contents of the package. It should contain:
1-Panel pet door
1-Center Post Weather Seal Strip (vinyl strip)
1-Dead bolt or Pin-type lock
1-Foam weather strip (for edge of pet door)

Open the Sliding Glass Door and Install the Pet Door Against the Jamb:
Run the foam weather strip up both sides of the pet door.

Install the pet door. Loosen the thumb screws. Then insert the spring mechanism at the top of the pet door into the top track. Push up against the spring and swing the bottom of the pet door onto the rail at the bottom. Then tighten the two thumb screws to lock the pet door in place.

Mount the center post weather strip. This vinyl piece will prevent air leaking between the sliding door and the stationary panel. It mounts on either the leading edge of the stationary panel or on the trailing edge of the sliding panel. In either case, clean your frame to ensure good adhesion and trim the vinyl piece with scissors for a good fit. Peel off the protective paper and stick on the weather strip being careful that the vinyl only lightly touches the opposite glass to avoid unnecessary drag.

Panels 80" and less come with a "pin" or "dead bolt" type lock.
For a "pin" type mount the pin-lock to lock your sliding door against the pet door. With the pet door in place and the sliding door against it, drill a  ³/₁₆" hole through the track wall and the frame of the sliding door at the top near the center post. When the steel pin is in place, the sliding door cannot slide.

For oversized panels where the top track is too high to reach for a pin lock, a threshold mounted dead-bolt type lock is included. Installation is similar to the pin-type locks.

Be sure not to drill into glass as it will shatter if you do!

If you prefer not to use the included lock:
Cut a piece of wood to place behind the sliding door to lock it against the pet door.  Your local hardware store will have other methods of locking a sliding door against the pet door as well.

Most of the time you can also install the pet door between the stationary panel and the other jamb. You'll have to examine your stationary panel to see how it is fastened in order to do this. There is no one single method. If your curtains and drapes allow this approach, it may be desirable to avoid changing an alarm system or to allow you to continue to use your existing sliding door lock.

If your pet door is slightly too tall or too short to fit in your track: To shorten the pet door, use a table saw, jig saw or hacksaw to cut down the flanges at the top of the pet door. Do not cut into the heads of the hex nuts at the top. To lengthen the pet door, remove the hex nuts and use washers to boost them up a maximum of 1/4". For more height, height extension pieces are available from Patio Pacific for a nominal charge.

You may also install the pet door in an outside screen track and open the sliding door for ventilation. If you have at least  ³/₄"  clearance between the pet door and your sliding glass door, you will be able to close the sliding door in front of the pet door.