Its phonation is voiceless, which means it is produced without vibrations of the vocal cords. In some languages the vocal cords are actively separated, so it is always voiceless; in others the cords are lax, so that it may take on the voicing of adjacent sounds.
It is an oral consonant, which means air is allowed to escape through the mouth only.
It is a central consonant, which means it is produced by directing the airstream along the center of the tongue, rather than to the sides.
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Verhoeven, Jo (2005), "Belgian Standard Dutch", Journal of the International Phonetic Association, 35 (2): 243–247, doi:10.1017/S0025100305002173