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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The IdeaCentre A600 all-in-one offers several connectivity options including high-speed WiFi, a 6-in-1 media card reader, side-mounted USB and FireWire ports with additional USB ports on the rear of the panel.

ENGADGET: Lenovo IdeaCentre A600 All-in-One Desktop unleashed