I bought this double injection in addition to the basic system because I think it is important that the oil lubricates both sides of the chain, rather than one with the basic system. I agree with previous comments: no problem to install, the manufacturer has really thought to provide all the staples, necklaces and other adhesives guides for tracking and fixing this injector is the best possible.
To you to position the proceeding to successive adjustments.
It's true that a notice would have been welcome in French but even without being very good in English it's OK with clear drawings and using a bit of his head! there is also on the canvas biker forums (French) detailing the operation with great pictures.