I carry 2 2x10 boards, roughly 4 feet long (probably more like 3 feet), ends cut at an angle. I used to carry 3 boards, but rarely had to use the 3rd.
I also have 2 bags of "Ramp Levelers", or as I call them Lego blocks, which are the same thing as the Lynx levelers although possibly not as heavy duty. On the rare occasion I need more than 2 boards for leveling, I have the lego blocks.
As per Soundguy's excellent post, the plastic lego blocks work much better if they sit on a hard surface such as a board.
Also, I actually use the lego blocks more for leveling the grill and picnic table than anything else! But whatever you use them for, they are very convenient to have on hand.
