This PetSafe White Aluminum Pet Door for Sliding Doors (model# PPA11-13130, Lowe's item #394411) is designed to insert into existing sliding door tracks, providing pets with independent access without permanent door modification. Unit measures 16" W x 86" H and accommodates large breed dogs. Includes the full pet passage door panel, mounting hardware, and manufacturer instructions. Item is like new in original box with no damage or missing components reported.