vt.钻孔
adj.埋头的
Hexalobular socket countersunk head tapping screws. 沉头内六角攻丝螺钉。
CROSS RECESSED COUNTERSUNK HEAD WOOD SCREWS B.S. 英制十字槽沉头木螺钉。
A tool for making a countersink. 做螺丝钉孔的工具
Countersunk, Checkered Head, Diamond Point, Polished. 沉头，花格帽，钻石尖，抛光处理。
A common usage is to allow the head of a countersunk bolt or screw, ... 马车螺栓（螺栓教练）：有一个圆顶或沉头，而小腿是由简短根据头方节突破。
