The carapace of the AC capacitor is round or ellipse with bolt at bottom, 2 or 3 terminals of metal hard insert, which are arranged in triangle or line and all can be tested.

端子形式为插片式，端子为三角形排列或一直线排列，外壳是圆形或椭圆，底部带螺栓的电容器均可测试。

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A hexagonal molded rubber head forms around the rounded head of the metal bolt insert.

螺栓头部采用六边形形状，内部附有金属。

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Slam latch is screwed onto latch support which is either screwed or welded to the door. Assembled without insert it can be opened with a tapered square key. Bolt has free stroke.

这种锁舌用螺丝装在锁支架上，而锁支架用螺丝固定或焊接在门上，无锁芯的装配时，可用锥形四方匙开启锁栓为自由行程。

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But invariably there is play between the threads of the bolt and the female insert because the teeth don't fit perfectly.

FORBES: Magazine Article