6 year guarantee against leaking.
From the day when the light was bought, in every year, it has to be sent back to the manufacturer to a check, if it necessary, to change the sealing ring.
The cost for returning the light to the manufacturer, has to be paid by the Costumer. The cost of the tests and the sending is 19 EUR/occasion. (It is only valid within the EU member countries.)
It is forbidden to disassemble the product, this can only be done by the manufacturer. Disassembling comes with losing the guarantee.