The manufacturer specifies the size as suitable for cats to 15 lbs. We would expect this pet door to be suitable for even larger pets and suggest you simulate the opening for any cats up to about 25 lbs to see if the size would work for them.

One collar key is included together with a 'break away' collar to hang the key from. Or you may use your own collar.

The flap is clear, unbreakable Lexan® (unbreakable polycarbonate) and measures 7" x 9". This is an excellent feature in a cat door.

It is self-framing from 1 ¹/₄" to 1 ³/₄" which covers all interior and exterior standard dimension doors.

The pet door may be installed in a thinner door by shimming the opening to at least 1 ¹/₄". Available in white frame only. 

Electronic control is in one direction only. 9 volt battery included.

Hot Tip:  This same pet door is available installed in a patio door panel for sliding glass door here.

Ideal Pet Products 'E' Door