| 摘要 |
A positioning device is provided which is adapted to be secured to the back edge of a picture frame or the like. The device comprises a pivotally mounted indicator arm adapted to freely hang in the vertical plane when the picture frame on which disposed is in a normal hung position. When the picture frame is horizontally level no portion of the indicator arm is visible from the picture front; when the picture is not level a portion of the indicator is visible to the picture viewer.
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