द्विवितस्तिररत्निः प्राजापत्यो हस्तः ॥ कZ_०२.२०.१२ ॥
dvivitastiraratniḥ prājāpatyo hastaḥ
Two vitastis make an aratni; this is the prājāpatya hasta (the standard ‘cubit/hand’ measure).
It enables predictable scaling from small to large measurements, preventing manipulation in bills of quantity and labor/output reporting.