这是一种三位数字的代码，印在信用卡的背面，多数，但不是所有的电子零售商在进行买卖交易是都要求提供这一代码。

That's the three-digit code on the back of every credit card that most, but not all, e-retailers ask for when making a purchase.

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电子版证书包括PDF格式的钱包卡和思科证书，印在证书上的16位验证码以及电子邮件形式的祝贺信。

Electronic edition certificate includes letter of the purse card of PDF format and Cisco, imprint in the congratulatory letter of the code of 16 test and verify on certificate and email form.

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不同的技术可帮助实现此直接印刻的工艺，如激光/化学雕刻、点式打标和喷码打印技术。

Different technologies are available to directly mark objects: laser / chemical etching, dot peening and ink jet printing.

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