Those guanhu who developed their skills and were promoted to Minister Steward (Shaofu) of the Court of Sacrificial Worship were called 'gonghu' or 'lehu' (gongle) and received special treatment.
官戸中技能をそなえ少府・太常寺に上番するものを工戸・楽戸（工楽）と呼んで特別扱いとした。