My pair of jets has just arrived from Poland. Four days, including a weekend is pretty impressive. Can't get out there to fit them just now, as it's raining. Looking at them, there is a small hole just to the side of the fan jet, which I am presuming is the adjuster. I hven't examined it too closely yet, but am guessing it takes a small allen key. Can anyone confirm this is the adjuster, and if so, which way it works; i.e. clockwise for up etc? EDTE: Soon figured out the adjuster; in fact, it took a tiny torx bit. The jets are fitted and working. As per the guide, I packed them using cardboard and once I'd got them positioned, applied liberal quantities of PVA adhesive. I've left the cardboard in place while the adhesive goes off. Whole process took half an hour, and I am a useless clutz. Someone who knows what they're doing and has a normal supply of hand/eye co-ordination will manage it in half the time.