Features: Durable not easy to rust This is the metal plate attached to the underside of the base Helps to strengthen the bottom of the for tour pack increase its service life Enhanced secure installation support on mounting luggage racks Easy installation: Mount directly to the bottom of the mounting luggage rack with pre-drilled holes in line with the for tour pack holes Item name: universal luggage box for case trunk tail box quick release base No instructions available ,easy to install back on original position Specifications: Material:PP Size:Approx 18 5x17 5cm/7 28x6 88inch Size:Approx 23 5x25 5cm/9 25x10 03inch Color:Black Note: 1 Please allow 1-2cm errors due to manual measurement, make sure that you do not mind before you order 2 Due to the difference between different monitors, the picture may not reflect the actual color of the item Thanks for your understings Package includes: 1 Set Tail Box Fixing Plate