Feature: 1. FITMENT: 4 red holes for Sprinter 2007 to 2018; 4 yellow holes for Sprinter and Metris 2019 to 2020; 6 purple holes for Sprinter 2002 to 2006; 4 green holes for Transit 150 250 350 2014 to 2023; 6 blue holes for Promaster 2014 to 2020. 2. SWIVEL SEAT BASE: This chair seat base features four steering clamp slots that effortlessly upgrade a fixed seat to a swivel seat, allowing drivers easy access and improved interaction with other passengers. 3. HEAVY DUTY CONSTRUCTION: Crafted from robust carbon steel and hot rolled steel, this 360 degree seat base is designed for exceptional strength and durability, making it a dependable choice for any vehicle. 4. RUSTPROOF FINISH: The seat rotating base is coated with a black powder finish that effectively prevents wear and tear, ensuring the base remains long lasting and able to withstand the test of time. 5. STABLE SEAT FIXATION: The heavy duty design of this seat base ensures secure seat fixation during vehicle operating, ensuring the safety and comfort of driver while on the move. Specification: Item Type: Heavy Duty Seat Swivel Base Material: Carbon steel + hot rolled steel Base Size: Approx. 460x460mm / 18.11x18.11in Rotation Angle: 0-360 degrees Rotation Direction: Forward or Reverse Application: Used for seat base modification, can transform the fixed seat into a swivel seat for easy adjustment of seat orientation, convenient for boarding or interacting with other passengers (only suitable for driver side) Installation Guide: If your seat is too large, additional transition plates may be required for installation, if your seat is too small, re drilling is needed, the installation of the seat base depends on the size of your seat Fitment: The following models can be installed directly without drilling 4 red holes for Sprinter 2007-2018 4 yellow holes for Sprinter and for Metris 2019-2020 6 purple holes for Sprinter 2002-2006 4 green holes for Transit 150 250 350 2014-2023 6 blue holes for Promaster 2014-2020 And also apply for T5 T6 (Re drilling required for installation on other models). Package List: 1 x RV Seat Base 8 x Screws 8 x Nuts Note: The installation of the turntable base is somewhat difficult. It is strongly recommended to seek assistance from professional engineers to ensure better shopping experience. Please pay attention to safety during the installation process.