If you need a butane thread adaptor, we can help at I Gas Direct. If you are looking for a butane bottle thread, we can fit your needs. This Butane Nut is the perfect butane thread nut. When it comes to finding a 21.8 adaptor, I Gas Direct is the place to go. Please contact us if you are searching for a 21.8 nut or a butane thread nut, a member of our team will be in touch.