Pressure Hose Advice Please

My pressure hose has two different lances that come with it. Although I haven't had any problem with using it I don't know what the difference is between the two.

One gives a rotary spray and the other gives a flat and wide spray. What should each one be used for? The instruction book didn't say anything about them.

My main use for the hose is to clean my patio.

I'm sure that there are many of you out there that know the answer and it will probably be quite obvious once you have explained it :D :D

 

Thanks Kandy but it would be difficult to show the difference in a photo. It is just the difference in the type of nozzle on each lance and they are a black type of plastic that probably won't show up. I'll try tomorrow if it is sunny. :D

 

Thanks Pro,
Having used both of them I can't actually tell the difference in the strength of the jets. Obviously the closer I move the nozzle to the paving the narrower and more forceful the jet is. Both of them take the occasional flakes of stone off the paving as they are a variety of sandstones. Some are a lot more porous than others and they are the ones that seem to get a lot more algae on them. I shall try the chemical next time.

Thanks