PlexiDor Performance Pet Doors Top Swing Sliding Track for Pet Doors with Flip Lock Accessory for use with steel security plate included with PlexiDor Pet Doors Sliding Tracks attach to interior PlexiDor frame Flip Lock feature secures steel plate and will not interfere with lock and key Works with PlexiDor Door or Wall Units in sizes M, LG and XL Available in Silver, White or Bronze