When the curtain is running, the hook will shake, and then it will make a sound
The distinction between the two is in the period of ` ` ` wire traction power, can not be used, ` ` ` belt traction during a power outage, you can pull.
Electric rail commonly used in the family is divided into two kinds: one is ` ` ` ` this ```{wire traction cheaper} is a price comparison in the ``{traction belt on}``
Electric rail ` needs a retractable motor connected with a power supply plate there is a ` ` ` ` ` ` `
