crown head piston(convex head piston) dome-head piston
Related Translations:
凸: Ⅰ动词(高出) bulge; protrude 短语和例子挺胸凸肚 throw out one's chest and bulge one's bellyⅡ形容词(高于周围) protruding; raised 短语和例子凸纹 raised carving or design; 凸花银瓶 [工美] a silver vase with a raised floral de