Revolving Warning Light Kuala Lumpur (KL), Selangor, Damansara, Malaysia.

Revolving Warning Lights are used as visual alerts. 
It is  arranged as to appear and disappear at fixed intervals, either by being turned about an axis so as to show light only at intervals, or by having its light occasionally intercepted by a revolving screen.
This can be done by electronic or mechanical motor. 
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