We stayed at an RV park one time where the owner worked at a sawmill and they had a variety of scrap wood free for the use - or taking. We left there with several blocks of wood that are basically 8"x8"x8". I attached cheap cast iron handles to them and they go everywhere with us.
I don't guess it's a proven theory, but for us it seems having the legs extended about 8" less than we would otherwise (along with the use of a 5th wheel tripod stabilizer) there is very little if any movement in our trailer generally.
Not sure what type of wood it is, but it's not an overly dense "hardwood" so it's reasonably light-weight and we simply toss them in the bed of the truck when we head out.
Robert & Estha Shiflet
'12 Columbus 320RS - 2015 Ford F-350 King Ranch & 2010 Ford F-250 King Ranch
Nights Camping 2012 & 2013 & 2014 & 2015: 458 ~ Nights Camping 2016: 95 So Far