Fueltheft is impossible after installing this aluminium anti-syphon system. The safety of the diesel is guaranteed till the top of the tank. The stainless steel part, which you could move upwards, makes it possible to refuel with an automatically fuelpistol. More information about out anti-syphon solution could you find on the website: www.protanktion.com. This version makes it possible to use the original filler cap. The internal proTANKtion® is mounted on the inside ring instead of the anti-splash valve. The needed anti-theft screws are included.