Optional accessory: power, LCD power display, switch.

可选配件：电源，液晶电量显示，开关。

youdao

Clothes hook is not furnished; available as optional accessory.

不配置衣帽钩，但可作为备选附件选配。

youdao

Optional accessory: aluminum alloy folding guardrail, rack, dining table.

可选配件：铝合金折叠式护栏，活动鞋架，翻倒式餐桌。

youdao

You can even track sleep with an optional accessory (see below).

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Both models include 270-degree swivel 921k-dot touch-enabled TruBlack LCDs and XGA OLED eye-level electronic viewfinders, along with Sony's new Multi Interface Shoe, which enables XLR microphone inputs through an optional accessory.

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While the strap on the back is an optional accessory, we see its appeal for securing the device in hand, and fully expect it'll be a popular add-on for enterprise customers.

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