First Time Use - broken RV Leveling Blocks

With the new camper I thought I should get leveling blocks instead of wooden planks. Well now I am going back to the wooden plank way. First time out of the box and I stacked 2 on the ground and 1 in the middle to give one side of my camper a little raise. Placed them under the front of the of each tire and snap crackle pop the first bottom one broke into a bunch of pieces. I think I will try the Andersen 3604 leveler before I go back to wooden planks. I will say that I called Camping World and no fuss or hassle and was issued a refund immediately. They said to dispose of them as it was not effective to ship my 2 sets back. Very impressed with that service. Just wished they carried the Andersen leveler to switch too.