I did have an issue with some of these coils, but contacted Apollo and they responded immediately and offered me money back or store credit. To me a company that right off the bat offers your cash money back is a great company. I chose store credit. I believe it was a quality control issue and that the manufacturer will do a better job going forward.

I have been using these coils for years. Best ones on the market

This is an old school core 5 years young with little modifications with the wick or upgrades by the manufacturer. It works with other manufacturers tanks but I don't know to what extent. Will it lose out threads or tank contacts of other brands? All i could say is that it worked with my previous tanks and yes if this was the upgraded version or if there ever was an upgrade at all can't tell. I don't want to open the blister packs I ordered but I know these are original or genuine it is sold by Apollo. I like the coolness that comes from this 2.5 ohm core when it works with my mint juice. As this is a single core, not so cloudy but enough to not fume in all holes and hack a cough. I'm considering the dual cores soon soon enough. In the market for an upgrade.

Affordable woork well and compatible with Kanger

Good price, and Can't tell any difference between these and more expensive Kanger brand.