I querried Thunderhawk Collectibles via email the other day. I got this response back rather quickly from Julie Erickson at Thunderhawk:
"The difference between these two lighters is the Juniors have an open spot (not shown in the photo because it is on the back side) where there is a small panel (3/8" x 3/8") covering the hole on the Supers. Also, the pattern on them is slightly different. Otherwise, they are the same size and operate exactly the same. Thanks for your questions!"
Methinks I'm going to pick up a Super Triplex lighter from them. Can't wait to get it!

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Splat