The strikers supplied work fine, but only AFTER you scrape off the stupid green coating they put on them. I filed the sides and edges so it was bare metal. The best strikers I've found (for all firesteels) are cut down hacksaw fine-toothed metal blades. It you scrape using the teeth you get fantastic sparks. But it eats up your firesteel much faster (wear is not an issue in an emergency situation though). The spine of my carbon steel knife throws lots of sparks off of these firesteels too. I have not tried a stainless knife however, but I would not expect that to be good in the first place. Also, the stupid string they attach the striker with is too short for best sparks. Get rid of the string and go at it with a less restrained scraping motion.