Both the attendance machine and external card reader are mounted on the wall. A mental wall or gate will shorten greatly the distance to punch card, even make it unable to work.

本考勤机和外置的打卡头都是安装在墙壁上使用的，但是如果安装在金属墙壁或金属门上，将明显缩短打卡距离，甚至完全不能打卡。

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When you get to work, you put your card in the punch clock, and it will print your starting time on the card.

你来上班的时候，把你的卡片放进考勤钟，它就会打出你的上班时间。

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In 1935 IBM landed a contract to tabulate employment for the Social Security system and put those dusty punch-card machines to work.

FORBES: Job Killers: A Rogues' Gallery