The Compendium of Caraka 8.3.8

8.3.8

ṣaḍdvādaśāṣṭāṅgulasaṃmitāni ṣaḍviṃśatidvādaśavarṣajānām/
syurmudgakarkandhusatīnavāhicchidrāṇi vartyā 'apihitāni caiva//

They should measure six, twelve, and eight finger-breadths
for those aged six, twenty, and twelve years;
their orifices should allow a mudga bean, a jujube fruit, and a pea to pass, and should be plugged with a wick.