Here is a list of some leading suppliers of plastic helical gears in the United Kingdom:

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Leading Suppliers of Plastic Helical Gears in the UK

1. The Gear Factory Ltd

   • Specializes in various gear types including plastic helical gears.
   • Website: www.gearfactory.co.uk

2. Direct Gears Ltd

   • Offers a range of gear solutions, including plastic gears.
   • Website: www.directgears.co.uk

3. RSD Gears

   • Provides custom solutions including plastic helical gears.
   • Website: www.rsdgears.com

4. NYC Gear

   • Focused on precision engineered gears, including helical types.
   • Website: www.nycgear.co.uk

5. Stock Drive Products (SDP/SI)

   • Offers a variety of gearing solutions including plastic options.
   • Website: www.sdp-si.com

6. Alpha Precision

   • Specializes in high-quality plastic components including gears.
   • Website: www.alphaprecision.co.uk

7. Gears & Motors Ltd

   • Supplies a selection of gears, including plastic helical designs.
   • Website: www.gearsandmotors.co.uk

8. KHK Stock Gears

   • Offers a wide range of stock gears, including plastic helical gears.
   • Website: www.gears-parts.com

9. Duralast Ltd

   • Focuses on custom plastic components including gears.
   • Website: www.duralast.co.uk

10. Bishop Gears

    • Provides precision gears including plastic helical models.
    • Website: www.bishopgears.com ```

This list provides a mix of companies that manufacture or supply plastic helical gears, with their websites for further exploration. Please verify the information and check for the latest offerings as companies can update their portfolios frequently.