The UV light in the pen cap provides a second authentication test by revealing the embedded micro-printed strip in genuine currency.

探测笔帽上的UV灯能够进行第二次鉴别测试，通过UV灯能显示出真钞的植入式的微印条。

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This is the cap of my fountain pen.

这是我的钢笔笔帽。

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The cap of the pen is missing.

那支钢笔的盖不见了。

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This number dictates the ratio between the pen cap and visible portion of the barrel.

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The cap of this pen doubles as a stylus tip, giving users the option to write with ink on paper in the iNotebook device and then quickly switch over to writing with a stylus in the app.

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The cap rings of the pen are encircled by a stylized roll of celluloid.

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