
Verplas VKC303 White In-Line Backdraught Shutter 100mm / 4"
VKC303
Verplas VKC303 White In-Line Backdraught Shutter – 100mm (4") for Ducting Systems
The Verplas VKC303 White In-Line Backdraught Shutter is designed to prevent unwanted airflow and draughts in 100mm (4") duct systems. Ideal for use in domestic ventilation, it allows airflow in one direction while sealing off reverse flow to maintain system efficiency.
- One-Way Airflow Control: Prevents backdraughts by allowing air to pass through in one direction only.
- Compact In-Line Design: Easily integrated into 100mm ducting runs without disrupting airflow.
- Improved System Efficiency: Minimises heat loss and maintains consistent ventilation performance.
- Low Maintenance: Simple plastic flap design for long-lasting, reliable operation.
- Neutral White Finish: Matches standard plastic ducting components for a clean, professional look.
Technical Specification
- Product Type: In-Line Backdraught Shutter
- Diameter: 100mm (4")
- Material: Plastic
- Colour: White
- Installation: Push-fit into ducting
✅ Maintain effective airflow and reduce unwanted draughts with the Verplas VKC303 In-Line Backdraught Shutter!

C/w Humidistat | N |
C/w Pullcord | N |
S4 - Size | 100mm / 4 Inch |
Product | Backdraught Shutter |
Type | In-Line |
Colour | White |
Mounting | Recessed |
Use | Domestic |
Thread Shape | Round |
Impeller Diameter | 100 mm |
Delivery Options:
- PRIORITY DELIVERY – Next Working Day (All items in stock and ordered before 3 pm) - £7.08 inc-VAT. (£5.90 ex-VAT)
- Orders Over £100 (before VAT): We offer free standard shipping on all orders shipped to UK mainland addresses
- Orders under £100 (before VAT): Our standard delivery fee to UK mainland addresses is £5.90 ex-VAT (£7.08 inc-VAT)
*Delivery charges to JE, GY, TR, BT, IM, IV, HS, KW, ZE and certain PA post codes are £12 ex-VAT for all orders (Prices subject to change).
Items requiring specialist shipping:
- Orders containing Solar Panels, Batteries and/or Inverters: Up to 50 qty will be dispatched on a pallet and incur a £120 ex-VAT delivery charge**.
**Delivery charges to JE, GY, TR, BT, IM, IV, HS, KW, ZE and certain PA post codes are £180 ex-VAT (Prices subject to change).
Contact us if you have any further questions.