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Pest Expert Formula C Cluster Fly Spray 5Ltr

£34.95 incl. VAT
£29.13 excl. VAT

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Qty From Qty To Unit Price
1 £34.95
2 5 £32.95
6 £29.95


Pest Expert Formula 'C' Cluster Fly Spray is a fast-acting cluster fly killer with a long-lasting residual that helps maintains long-lasting cluster fly control.

  • Fast-acting – kills cluster flies on contact
  • Long-lasting residual maintains cluster fly control for up to 12 weeks!
  • Apply to window frames, roof timbers and other alighting surfaces.
Product Information
Pest Expert Formula 'C' is the most powerful cluster fly killer spray available to the amateur market, offering both fast-acting and long-lasting cluster fly control to help eradicate a cluster fly infestation in your home, loft or roof space.

Formula 'C' Cluster Fly Spray should be applied to any alighting surfaces including window frames and roof timbers. Cluster flies will die on contact with the invisible insecticidal residue, which is effective for up to 4 weeks, offering extended protection from cluster flies.

Formula 'C' Cluster Fly Spray is water-based and low-odour, making it perfectly suitable for use in homes with children and/or pets, provided they are kept out of the area being treated until all surfaces are dry (2-3 hours).

The active ingredient in Formula 'C' is the powerful broad spectrum insecticide cypermethrin (0.1% w/w), which is also effective against a wide range of flying and crawling insects.

Each 5-litre container is sufficient to treat an area of approx 100m2.

Directions for use
Lightly spray roof timbers, sash windows, Velux windows, window frames and any other alighting surfaces or cluster fly harbourages. Try to avoid cleaning these surfaces as this will remove the protective residue.

When carrying out a cluster fly treatment to a large area, we recommend using one of our Pressure Sprayers to enable an even distribution of the Formula 'C' insecticide and help you achieve a professional application (see Related Products below).

Best used following treatment with a fumigation device such as a Pest Expert Formula 'P' Fogger or Smoke Bomb to flush out the initial cluster fly infestation. We highly recommend our Cluster Fly Control Kits as they contain a combination of our best cluster fly killer products including Pest Expert Formula 'C' Cluster Fly Spray, Formula 'P' Foggers or Smoke Bombs and Pest Expert Formula 'P' Powder and offer better value for money than purchasing these items individually. 

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Customer Reviews

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Reviewer: Ingrid from Cambridge   5 Stars

Order quickly delivered. Product works very well. I have used them for a number of years to kill Cluster flys in the Autumn, and they always work well.

Reviewer: Paul from Sunderland   5 Stars

Seems to work very well. After just one application flies have not reappeared. Recommended.

Reviewer: Kellie from Oxford   5 Stars

Great products that were very effective at removing the cluster fly problem. Very prompt delivery!

Reviewer: Jasmine from Lincoln   5 Stars

Easy ordering, website extremely easy to use. Very quick delivery. Not yet used product but it came very well packaged, boxed and undamaged. After the initial spray, the amount of flies dramatically reduced and the house is back to normal!

Reviewer: Clive from London   5 Stars

The product supplied worked very well and was delivered the next day. The flies in my loft have all died!

Reviewer: Peter H from York   5 Stars

Large size and fantastic value for money! The product worked well and I am once again Cluster Fly free. Happy days!

Reviewer: Eamonn from Grantham   5 Stars

Good product, did the job and excellent day! Would highly recommend.

Reviewer: Kerry Johnson from Plymouth   5 Stars

Pathetic looking smoke bomb but 24 hours later nearly every cluster fly was dead.

Both the smoke bomb and spray worked well. Flies could be flushed out and killed by spraying.

Reviewer: Nichola Popham from Oxford   5 Stars

Fly pest control

Very efficient, speedy delivery, excellent communication