Johnston has traditionally employed Herco Nylon Flex 50 flatpicks (old "Herco mediums"),https://www.jimdunlop.com/product/he210p-7-10137-01950-8 allowing for the right combination of flex and durability for his chukka-style rhythm. He said "I always use Herco medium because they don't break, and they take forever to wear out. Actually the worst thing you can do with a Herco is lose it. They are easy to hold on to as well and I do sweat a lot playing live. In fact, I usually eat the nickel off the strings right down to the brass (circa 1976)."
