一级头 yījítóu first stage Definitions Defs Origin Strokes Stroke Words Sentences Sents 一级头 一級頭 yījítóu first stage The first stage of a scuba diving regulator, which reduces high-pressure air from the tank to an intermediate pressure.
一级头 一級頭 yījítóu first stage The first stage of a scuba diving regulator, which reduces high-pressure air from the tank to an intermediate pressure.
