a级国产大片在线免费观看專業從事互動視頻_欧美日韩国产主播在线_欧美亚洲日韩理论片在线_中文字幕第二页_国产精品麻豆影院_在線觀看免費三級無碼_亚洲日韩av成人影视一区_(凹凸視頻)久久精品免费_军人野外吮她的花蒂无码视频_中国gay男男av毛片免费看

● The alarm whistle and the pressure gauge are integrated, located on the chest, and the whistle is easily recognized;

●High voltage activation and medium voltage alarm mode. The alarm duration is 4 times higher than the high-pressure alarm mode, reducing alarm gas consumption and prolonging the use time.