Here is a list of leading national suppliers of Polyolefin Crimped Hoses in the United Kingdom:

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Leading Suppliers of Polyolefin Crimped Hoses in the UK

1. Parflex
   Specializes in manufacturing high-performance industrial and hydraulic hoses.

2. Flexotech
   Offers a range of hoses, including polyolefin varieties, focusing on innovation and quality.

3. RS Components
   A global distributor supplying a variety of hoses and related components.

4. Hose & Fittings
   Provides hose solutions including crimped hoses, catering to diverse industries.

5. Dunlop Hiflex
   Known for a wide range of industrial hoses including polyolefin products.

6. Hose(world)
   Specializes in various hose types and offers custom crimping solutions.

7. Parker Hannifin
   A leading global manufacturer of motion and control technologies, offers a wide selection of hoses including polyolefin.

8. Suttons Group
   Engages in the distribution of hoses, fittings, and pipelines, with a comprehensive product range.

9. Techfluid
   A supplier that focuses on high-quality industrial hose solutions.

10. Sae 100 R7/8 Ltd.
    A company dedicated to the production and supply of hoses for various applications, particularly focusing on thermoplastic products.

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These companies represent a mix of manufacturing and distribution capabilities within the UK for polyolefin crimped hoses, providing various solutions for industrial needs.