The second, called electrochromic, requires voltage to switch the transparency from clear to opaque.

FORBES: Dynamic Windows Improve Efficiency, Human Experience in Buildings

In a 2004 corporate report Toyota said the key to the improvements was its decision to switch to a high-voltage system.

FORBES: OutFront

In order to fully exploit the sound potential of the HDVD 800 with any audio source, a rotary gain switch at the rear of the unit provides simple adaptation of the amplifier output to the audio input voltage.

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