C77 Electric Overhead Blackout Unit
A motorised, tensioned blackout system for suitable roof windows where both access and light exclusion matter.
Explore product : C77 Electric Overhead Blackout Unit
Product imagery is illustrative of the system. Confirm the finish and options in your quotation.
Blackout units
C76 Crank Overhead Blackout Unit
Product reference C76
A tensioned blackout assembly for suitable sloping or horizontal roof windows, with manual crank operation.
At a glance
- Designed for suitable overhead glazing
- Geared crank and spring-tensioned fabric
- Enclosed channels with light-sealing details
UK-wide supply and installation enquiries. We confirm the configuration, availability and fitting requirements for your project.
Product overview
About this system
C76 combines an overhead draw-tape mechanism with the enclosed detail of a blackout unit. A sprung fabric barrel and a geared drive move the bottom rail across the opening, while side channels, baffles and pile seals address light around the edges.
The detachable crank allows manual operation from an accessible position. It is an option to assess for roof glazing where the project requires a defined blackout arrangement but a motor is not the preferred method of control.
Assess roof geometry and structure
The system needs appropriate mounting space at both ends and along the sides. Provide a drawing of the roof opening where possible, including the reveal depth, angle and any opening or ventilation hardware.
Agree operation and maintenance access
A detachable handle must be usable from a sensible position. We also need to consider how the blind can be reached for fitting, adjustment and future servicing, particularly above stairs, furniture or sensitive equipment.
The technical details
Specification
| Operation | 1:5 geared crank with draw tapes |
|---|---|
| Headbox | 100 × 100 mm (height × depth) |
| Barrels | 53 mm drive barrel and 57 mm sprung fabric barrel |
| Side channels | 75 × 20 mm (width × depth) |
| Light-control detail | Blackout fabric, baffles and pile seals |
Limits depend on the selected configuration. Use the relevant product documents and the agreed written specification for your order.
Options to discuss
- Fixed crank handle
- Alternative RAL finish by enquiry
Check before ordering
- Suitability and size must be confirmed for the actual roof opening and fabric.
- Blackout performance depends on the complete perimeter installation.
Product resources
Technical documents
Defiant product brochurePDF · 1.6 MB · Opens in a new tabC76 technical datasheetPDF · 218 KB · Opens in a new tabC76-C77 Overhead Blackout: Crank/Electric — fitting instructionsPDF · 253 KB · Opens in a new tab
Original manufacturer documents retain their branding. Confirm the product version and any additional warranty with your quotation.
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Explore product : C56T Crank Overhead Cassette Blind
R56 Overhead Crank Roller Blind
A manually geared overhead roller using spring tension and draw tapes to move across roof glazing.
Explore product : R56 Overhead Crank Roller BlindLet’s work through the details
Get a quote.
Plan your project.
Share the products you have in mind, or tell us what the space needs to do. We’ll help you establish the specification and the next step.
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- UK-wide supply and installation enquiries
- Supply-only products and component orders
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