Elastic

Stretchy bands for holding fabric. The traditional way that people use rubber bands is to spiral a shirt, scrunch or an accordion fold. Most often, you'll see people using liquid dye, in bottles, when they are using elastics to hold a folded shirt in place.

I don't often use rubber bands anymore because I am doing geode tie-dye or flowy ice dye, and neither of those uses elastics. But sometimes they can be really helpful if you need to section off some parts of the geode tied shirt, if you want to group together a bunch of the bundles for applying dye with the cold mist method.