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Pest Expert Formula C+ Cluster Fly Spray 5Ltr

£31.95 incl. VAT
£26.63 excl. VAT

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Qty From Qty To Unit Price
1 £31.95
2 5 £30.95
6 £29.95


Pest Expert Formula C+ Advanced Cluster Fly Killer Spray is the new and improved formulation of our bestselling original product, Formula C. Formula C+ Advanced is a ready-to-use triple action cluster fly killer, with a long-lasting residual that maintains cluster fly control for up to 12 weeks. Its unique combination of actives make it the most powerful cluster fly spray available to the amateur market, and the ultimate insecticide for anyone wanting fast and effective eradication of any size cluster fly infestation.

•    Fast-acting: Rapid knockdown
•    Low-odour: No smell during or after use
•    Non-staining: Will not damage household furnishings
•    Long-lasting: Residual maintains cluster fly control for up to 12 weeks
•    Increased coverage: 5L now treats up to 250m2 in a single application

Product Information
As market leaders, our latest innovative formulation now incorporates two additional active ingredients. The first is pyriproxyfen, a ground-breaking insect growth regulator that cleverly works by halting the progression of the cluster flies lifecycle development from juvenile to adult, resulting in an inability for the fly to reproduce, and therefore ensuring there is no increase in numbers.
The second is the addition of chrysanthemum cinerariaefolium extract, a natural pyrethrum, which when combined with the existing concentration of cypermethrin has a synergistic effect, helping to deliver an even faster knockdown and longer-lasting residual for ongoing control of all life-cycle stages.

With approval for both professional and amateur use, this professional-grade product can also be used safely in the home. Formula C+ Advanced is easy to use and can be applied directly to window frames and exposed beams as it is water-based and non-staining, so will not cause any damage.

Being low odour and free from solvents, Formula C+ Advanced is 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).

Formula C+ Advanced now offers an increased coverage of up to 50 sq m per litre, so a 5L canister will be sufficient to treat a surface area of up to 250 sq m.

One application should be enough for a successful cluster fly treatment. However, to eradicate a particularly heavy carpet beetle infestation then a second application may be required.

As a broad spectrum insecticide, Formula C+ Advanced is also highly effective against a wide range of flying and crawling insects including bed bugs, cockroaches and fleas.

To achieve a thorough and professional application, we provide a free trigger hose sprayer with the 5 Litre bottle (one per order).

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.

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