Thread Magic Thread Conditioner
I started using thread conditioners back in 2018 -- and I really enjoy them. I don't use them all of the time, but I find with some threads, conditioning them helps them look a little more neat and tidy, and you get less drag while you're stitching (your thread glides through so SMOOOOOOOOOTHLY). The second picture shows what the container looks like -- instructions for use come with the packaging. The size of the container is about the size of a US quarter across the top.