Doubly articulated consonants are consonants with two simultaneous primary places of articulation of the same manner (both plosive, or both nasal, etc.). They are a subset of co-articulated consonants. They are to be distinguished from co-articulated consonants with secondary articulation, that is, a second articulation not of the same manner. An example of a doubly articulated consonant is the voiceless labial-velar plosive , which is a and a pronounced simultaneously. On the other hand, the voiceless labialized velar plosive has only a single stop articulation, velar , with a simultaneous approximant-like rounding of the lips. In some dialects of Arabic, the voiceless velar fricative  has a simultaneous uvular trill, but this is not considered double articulation either.