Several plastics have a multitude of different fleck patterns. Blue fleck, black fleck, red fleck, purple fleck, gold fleck...etc.

What is the difference and what is the impact?

Thanks all.

to me its always been just another variation in color, maybe even an attention grabber. if i ever find another bag with a yellow transparent worm with gold flecks ill buy out the store haha

Fleck is just another way to effectively match the hatch IMO. On my home lake the shad all have a blueish tint to them. Anything with blue fleck or glitter is money.