It was narrated from 'Ammar bin Yasir that:
The Messenger of Allah said: Part of the Fitrah is rinsing out the mouth, rinsing out the nostrils, using the tooth stick, trimming the mustache, clipping the nails, plucking the armpit hairs, shaving the pubic hairs, washing the joints, washing the private parts and circumcision.' (Da'if) Another chain with similar wording.