The wooden bolt heads are arranged in alternating geometric patterns-specifically an eight-studded circle and a square with inverted corners.

木螺栓头被设计在交替的几何图案中——特别是一个镶嵌圆形和一个正方形倒角。

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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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Mesh column connection with the use of semi-circular bolt head square neck, with anti-theft rings and washers, to prevent the separation can be artificially demolition.

网片与立柱的连接采用半圆头方颈螺栓，配以防盗垫圈，能防止隔离栅被人为地随意拆卸。

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