I bought one of the tables that fold in half...when folded it is the size of a card table so when you unfold... twice the size...anway the legs are curved and I went the the hardware store and bought a 6 foot piece of pvc pipe..2 inch...cut into 12 inch (any size to get the height you want)pieces and they fit on the legs of the table...with the curve of the legs the pipes only go so far...12 inches give me the height I want but to low for my 5'9" daughter....just adjust for your self....I got my table at SAMS.
I also found out the pieces of pipe fit inside the table when folded up. Great storage. Good luck.