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 used to use long series of boards for both tires of elevated side but now use two shorter ones - one for each tire. Cut just short enough fit one between tires before going up on ramps.
Viewing side to side level attached to front of TT before leveling lets me know how many boards will be needed.