non-return finger

... non-retractable fin stabilizer 非收放型减摇鳍装置 non-return finger 单向安全销装置 non-return flap valve 止回瓣阀 ...

finger-英汉词典... ... nimble fingers 灵巧的手指 non-return finger 单向安全装置 not lift a finger {v.}不尽举手之劳 ...