Pet Door Products Is Your Pet Door Solution For Vinyl Sliding Glass Doors. We Are An Exclusive Pet Door Manufacturer In The Usa, Specializing In Our Pet Door Conversion System For Your Vinyl Patio Door. Replace Your Existing Vinyl Sliding Glass Door Unit With One That Has A Dog Door Or Cat Door Built Right Into It. Give Your Pet The Freedom They Deserve! the Energy-efficient Design Of The Replacement Sliding Glass Pet Door Conversion System Allows You To Leave The Pet Door Open. If You Need To Keep Pets Inside, A Simple Door Insert Helps “lock” The Door. Pet Door Products Is The Manufacturer, Not The Dealer; This Means There Is No “middle Man Mark-up.”