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Pest Expert Formula C Cluster Fly Spray 1Ltr (Free Safety Mask & Gloves)

£9.95 incl. VAT
£8.29 excl. VAT

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Qty From Qty To Unit Price
1 £9.95
2 11 £9.59
12 50 £8.99


Pest Expert Formula 'C' Cluster Fly Spray is a fast-acting cluster fly killer with a long-lasting residual that helps maintain 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 you 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 12 weeks, offering extended protection from cluster flies.

Formula 'C' 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 one litre trigger spray is sufficient to treat an area of approx 20m2.

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: Joe from Lincoln   5 Stars
Quick delivery and the spray seemed to do the trick. All in all, very pleased.

Reviewer: Simon from Kettering   5 Stars
Very good service. Spray arrived the next day and cluster flies disappeared. Couldn't ask for more!

Reviewer: Ian from Manchester   5 Stars
Excellent service impressive delivery. The product was easy to use and contained full instructions - certainly killed the flies in my loft. Would definitely recommend this company and would use again if needed.

Reviewer: Ian from Falkirk   5 Stars
brilliant service... brilliant product, cluster flies eradicated.

Reviewer: Stephen from Loxley   5 Stars
I needed to get rid of flies in the loft and after reading positive reviews I ordered the Formula C, I ordered one afternoon and they arrived the next morning, fantastic delivery. The instructions were clear and product very effective. Excellent service.

Reviewer: Geoff from South London   5 Stars
Really happy with my purchase! Less flies and a very competitive price!

Reviewer: Lee from Glasgow   5 Stars
Great product and great price! Long-lasting residue so should keep the flies away for a while!

Reviewer: James from Stratford   5 Stars
Used this spray around the window frames and eaves and have noticed a huge decline in flies around the property - an A1 product!

Reviewer: Katie Pressdee from SWANSEA   5 Stars
Great service, quick delivery. Would shop with the company again. Products were easy to select from the on-line store, purchase and delivery details were easy to complete and the products arrived quickly and in good order. Would repeat purchase from the store again

Reviewer: Ron Bevan from Cowbridge   5 Stars
Good service good product Totally satisfied with price and service

Reviewer: Jean Tooth from Balen   5 Stars
Flies. what flies I have used this product and it works very good,

Reviewer: Mrs Diane Lockley from kilgetty   5 Stars
Troubled with cluster flies then this product is the answer We have had the problem of flies getting into the bedrooms through the velux windows for years. The beginning of this year seemed to reach a peek. Desperate I searched the internet and then found this company and read through the product range. This is how I found out that we had a 'cluster fly' problem. Once I had the product I coated the window frames and surrounding roof tiles according to the instructions. I could not believe the results. NO FLIES. I kept opening the velux to check. 5 months and still no flies. Brilliant

Reviewer: Roy Groom from Ipswich   5 Stars
Excellent Excellent service for a very effective product.