The bottom one in that picture is unaltered (the way they come in the package). All the others I have pushed various colored plastics/foils into the cavity of the body to add color. One even has a "worm rattle" in it (as pictured below):
http://www.crappie.com/crappie/attac...attle-trix-jpg
And one could also force Nibbles or scent paste into the hollow body ... adding scent and/or color.
Here's the website :
Product Categories Flashtrix ... and do notice that the smallest version is 3" long (that's what these are, and that's a 1/16oz ballhead weedless jig with a #2 Aberdeen hook inserted into the Flashtrix pictured).
I'd be very interested in your reports/accounts of using these baits !!
I bought them because I thought they looked a lot like a Silverside .. which most of our local lakes have, and which I used to fish for Crappie with. Silversides look like this (but ours have a more greenish tint to their backs):
http://calfish.ucdavis.edu/files/79580display.jpg