Star two part reloading powder measure. Made of two parts of aluminum and I think the other part is steel. It has 9/16 by 27 threads to match up with all star threads. I don't know who makes this shut off but is seems to work fine. As I stated with my other shut offs I have for sale on e - bay I am down sizing because of my age. Look at the pictures and ask questions. I will do my best to answer any that I can. Good Luck and have fun.