thank you all for the input,seems to have answered a few of my questions, i was under the impression that you just pressed a button and hey presto van levels itsef up,i have heard from caralevel today at long last, and they inform me that blocks would still probably be needed if canver is more than 3', in reply to anns remark, there's nothing wrong with levelling manually with blocks, it's just that i am so lazy, and i like gadgets........lol........once again thank you everyone.