C76 Crank Overhead Blackout Unit
A tensioned blackout assembly for suitable sloping or horizontal roof windows, with manual crank operation.
Explore product : C76 Crank Overhead Blackout Unit
Product imagery is illustrative of the system. Confirm the finish and options in your quotation.
Blackout units
C77 Electric Overhead Blackout Unit
Product reference C77
A motorised, tensioned blackout system for suitable roof windows where both access and light exclusion matter.
At a glance
- Powered operation for overhead glazing
- Tensioned fabric with draw-tape drive
- Dedicated blackout channels and sealing details
UK-wide supply and installation enquiries. We confirm the configuration, availability and fitting requirements for your project.
Product overview
About this system
C77 moves a blackout fabric across an overhead opening using a 230 V AC motor, spring tension and draw tapes. The assembly includes twin barrel functions, side channels, baffles and pile seals to control the fabric and the light paths around it.
Powered operation suits glazing that is beyond practical manual reach. We assess the roof opening, electrical supply and control arrangement as one project, with the final dimensions and fabric confirmed before an order is placed.
Plan for the room’s use
If the blind serves a presentation, clinical or specialist space, explain any light-level requirement and how the room is controlled. This helps us define the scope and identify whether an acceptance check is needed after installation.
Leave service access
The motor, guides and fabric need to remain serviceable after the room is finished. Access height, suspended ceilings and equipment below the opening can affect both the installation method and future maintenance arrangements.
The technical details
Specification
| Motor | 230 V AC |
|---|---|
| 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
- Remote or grouped controls
- Alternative RAL finish by enquiry
Check before ordering
- The roof geometry, fabric and fixing surfaces must be assessed before supply.
- Final light exclusion depends on the complete installation and surrounding building details.
Product resources
Technical documents
Defiant product brochurePDF · 1.6 MB · Opens in a new tabC77 technical datasheetPDF · 735 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.
Compare your options
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A motorised, tensioned cassette with Tracker channels for suitable rooflights and overhead glazing.
Explore product : C57T Electric Overhead Cassette Blind
C75 Electric Blackout Unit
A mains-powered blackout assembly with an enclosed roller, side channels, baffles and pile seals.
Explore product : C75 Electric Blackout UnitLet’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.
- Free initial estimates by email or WhatsApp
- UK-wide supply and installation enquiries
- Supply-only products and component orders
Prefer a conversation?07849 709975
Monday–Friday, 9am–5pm
Online enquiries at any time.
We aim to reply within 24 hours. Appointment dates and any specialist installation requirements are confirmed by our team.