Here is the links for 2 different ones
http://www.northerntooluk.com/products.asp?partno=22824E 7.3mtr
http://www.northerntooluk.com/products.asp?partno=22818E I'm no expert with the lance yet, I've had mine a couple of weeks, but already used it on a few, it is heavy and I was going to buy the harness, but I have had to many Negative responses towards the harness so I decide not to buy it.
There is no difference in the pressure that I have noticed with 4 of the jets, there just set at different angles 0° 15° 25° 40° Orifice Size: 3.0
so its what ever angle you feel comfortable using, the last jet is the low pressure one and I have used this one for swilling through the gutters if there is no rubbish in them.
I do the facias and soffits with high the pressure jets, whats the point in buying it, if you use a brush instead?
Just take extra care when doing soffits with lots of vents in, My own is like this so I did do my own just to see the results, I went to my loft and found no problems with water, just make sure you fire upwards and not at an angle that would fire the water into the loft area.
also take care you don't fire the jets underneath the tiles, this could also go into the loft.
These are just my findings over the past couple of weeks, but I'm sure you'll get the pro's on later.