roof bars

A retractable roof is a roof system designed to roll back the roof of a structure so that the interior of the facility is open to the outdoors. Retractable roofs are sometimes referred to as operable roofs or retractable skylights. The term operable skylight, while quite similar, refers to a skylight that opens on a hinge, rather than on a track.
Retractable roofs are used in residences, restaurants and bars, swim centres, arenas and stadiums, and other facilities wishing to provide protection from the elements, as well as the option of having an open roof during favourable weather.

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