EDIT Related Characters
Derived from U+0E04 by adding a kink at the top.

This derivation was copied in the derivation of Tai Tham U+1A24 from U+1A23, and this is reflected in the relation of U+1986 and U+1985 in the derived New Tai Lue script.

 Richard W  :  Richard W 

EDIT Phonetics Low class consonant only used syllable-initially, where the sound is believed to have originally been [ɣ], becoming [x] with the great consonant shift. The sound then merged with the sound of U+0E04, and the consonant then ceased to be used in spelling.

 Richard W  Richard W