Kwikfish, once known as flatfish...
two different lures made by two different companies back in the day.
Kwikfish where made in Canada and Helin Tackle was made first in USA (if I remember correctly) and now Kwikfish are made offshore while Flatfish are North American made.
They have a different balance and sit differently in the water. Larger salmon sizes are different shapes and have different action with Kwikfish being much more salmon back trolling orientated with a tighter action. So much so in fact Yakima Bait has come out with their Mag Lip plug to target salmon and steelhead and compete better with Kwikfish and another kwikfish copy from Brad's Fishing gear called "Killierfish".
Because of manufacturers moq's there is now a much larger color selection of Flatfish available than kwikfish. If someone is going to back troll or anchor and toss them out the back of the boat they should check out the Mag Lip line up. they work very well and recently caught a few steelhead back trolling them.