The larger ones you are talking about are called "Tora" tubes and are super popular out west where the largemouth feed on stocked rainbow trout. The 5" and 6" versions are called Magnum Squidzits.
Here is a link from Cabela's that will put you right on them!
http://www.cabelas.com/products/Cpod0002785.jsp
Believe it or not I used to cast those 5 and 6" ones to bedding largemouth back in my tournament days when they were totally ignoring the small stuff.
Russ
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