There are two main types of senko hanabi.
They are the subote botan, made with straw, and the nagate botan, made with washi (handmade Japanese paper).
Subote botan is the original form of senko hanabi, and it has been a favorite mainly in Western Japan, where there is a lot of rice straw available.
Nagate botan sparklers are made in the Kanto region where a lot of paper is made, and where washi was used in place of straw.