\nobreakspace \ideographicspace \ideographichalffillspace \twoperemspace \threeperemspace \fourperemspace \sixperemspace \figurespace \punctuationspace \breakablethinspace \hairspace \zerowidthspace \zwnj \zwj \narrownobreakspace

or just their utf representation

Which of them is like \hairspace, but not breakable? Or where can I read all the properties of this commands? Huseyin