When ergonomics took off in the mid-1990s, King came up with a keyboard tray that had no knobs.

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When your smartphone keyboard fits in your hand, the armrests on your seat become a de facto keyboard tray.

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The BulletTrain Express is a wireless keyboard lap tray, perfect for your Mac Mini-as-Home Theatre PC.

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The Explorer's battery-operated keyboard is located on a tray table that folds out of the recliner's left arm.

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When used on a desk, table, or airplane seat tray, with the kickstand holding the screen upright and the keyboard cover with movable keys, the Pro is a serviceable laptop, especially since, unlike on an iPad or Android tablet, you can use full-fledged PC programs.

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