If you are using the Wide mouth ones, I would start with the HTP 126 and then try the HTP 1212. Make sure to test with the color and FO % you plan on using. edit: oh yeah, and make sure you test burn in 4hr increments. Be patient, you may not reach a full melt pool on the first or second burn, but by your third or fourth burn, as the jar tapers down; it will get hotter and eventually burn the left over wax from up top. As long as the flame seems strong and does want to go out, you should be fine.