khw became first [χw] with unvoiced w. Parallel to the development of khy this became in PQ a spirantal voiceless w [ƕ]. It was more tense with closer lip-aperture and more friction than the voiceless wh of English. This combination was in CE rare medially, but not uncommon initially. It is here transcribed hw.
In later Vanyarin pronunciation hw became f, but remained distinct from f in Noldorin and in the Exilic TQ.