I saw these a couple months ago. After our last trip with trying to get wood planks under the one side to get the TT level I searched and found these easy to use trailer levelers. I contacted Anderson...
I would be interested to hear how they work, especially on softer surfaces such as grass or plain earth. They may work on asphalt but my doubt is in getting the chock underneath.
I have used leveling blocks for years with good success. Never used planks.