Here’s a list of leading national suppliers of black fittings in the United Kingdom:

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Leading National Suppliers of Black Fittings in the UK

1. British Steel

   • Website: britishsteel.co.uk
   • Description: A major supplier of steel products including black fittings.

2. Dura Composites

   • Website: duracomposites.com
   • Description: Offers a range of composite black fittings for various applications.

3. Wavin

   • Website: wavin.com
   • Description: A leading manufacturer and supplier of plastic piping systems, including black fittings.

4. Hepworth Plumbing

   • Website: hepworthplumbing.co.uk
   • Description: Provides a wide range of plumbing solutions, including black fittings.

5. BSS (Wolseley UK)

   • Website: bssgroup.com
   • Description: A supplier of plumbing, heating, and pipeline solutions including black fittings.

6. Valves Online

   • Website: valvesonline.co.uk
   • Description: Specializes in a variety of valves and fittings, including black fittings.

7. Screwfix

   • Website: screwfix.com
   • Description: A leading retailer providing various construction materials, including black fittings.

8. Brodie Plumbing Supplies

   • Website: brodie.co.uk
   • Description: Offers plumbing supplies and accessories, including black fittings.

9. Ideal Plumbing & Heating Supplies

   • Website: idealheating.com
   • Description: Supplies a range of plumbing and heating products, including black fittings.

10. Plumbase

    • Website: plumbase.co.uk
    • Description: A nationwide supplier of plumbing and heating materials, including black fittings. ```

Please verify the most up-to-date availability and product offerings on the respective websites.