Here is a list of leading national suppliers of extension drills in the United Kingdom formatted in Markdown:

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Leading National Suppliers of Extension Drills in the United Kingdom

1. Bosch Power Tools

   • Website: bosch.co.uk
   • Overview: A leading manufacturer known for its high-quality power tools and accessories.

2. DeWalt

   • Website: dewalt.co.uk
   • Overview: A reliable brand providing durable tools and accessories for professionals.

3. Makita

   • Website: makita.co.uk
   • Overview: Offers innovative power tools and accessories, including extension drills with a focus on performance.

4. Tiger Tool International

   • Website: tigertool.com
   • Overview: Specializes in heavy-duty tools for the automotive and industrial sectors.

5. Screwfix

   • Website: screwfix.com
   • Overview: A retail chain that supplies various tools and accessories including extension drills.

6. Toolstation

   • Website: toolstation.com
   • Overview: A retailer providing a wide range of tools and fittings, including extension drills.

7. Aeg Power Tools

   • Website: aegpowertools.co.uk
   • Overview: Known for high-performance power tools and accessories for both professionals and enthusiasts.

8. B&Q

   • Website: diy.com
   • Overview: A major home improvement retail chain that offers a variety of tools including extension drills.

9. RS Components

   • Website: rs-online.com
   • Overview: A global distributor of electronic, electrical, and industrial components with a selection of tools.

10. Amazon UK

    • Website: amazon.co.uk
    • Overview: An online marketplace with a vast range of extension drills by various brands. ```

This list includes companies that are well-known for supplying extension drills in the UK, encompassing both retail and manufacturing.