Rubber O-Rings 21mm (10 pack)

£1.98 Excl. Tax: £1.65
63 in stock 63 in stock In stock and ready to ship. See our Shipping and Stock page for more info.

When in stock, UK approx 2-5 workdays, other countries see shipping page


Small 21mm diameter super strong nitrile rubber O-rings. These can be used as paraglider line-tidies, to prevent lines moving on riser maillons, or to stop a pair of Brummel hooks coming undone, for example.


Model Status: Current model



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These super strong nitrile rubber O-rings are used by some paragliding manufacturers as "line tidies", to keep your main lines snugly positioned on their maillon. They prevent the lines looping around the maillon gate and crossing over each other.

  • UV resistant
  • Outer diameter 21mm
  • Inner diameter 16mm
  • Thickness 2.5mm

Used as paraglider line-tidies for riser maillons

Open the maillon and take the lines off, being very careful to keep them in the same order for reattaching later. Put the maillon through the O-ring and put one twist in the O-ring (see image). Pass the lines through the O-ring and loop them back on to the maillon as they were before. Put another loop in the O-ring and loop back on to the maillon (a bit fiddly).

Suitable for

21mm O-rings are suitable for use with the following shape and size maillons:

  • Delta 3.5mm
  • Delta 4.0mm
  • Standard Oval 2.5mm
  • Standard Oval 3.0mm
  • Standard Oval 3.5mm

Used to stop a pair of Brummel hooks coming undone

Twist the O-ring into a double-loop and slide it over one of the Brummel hooks, such that it sits below the Brummel hook joining slit. Attach the second Brummel hook to the first and then slide the double-looped O-ring up such that one loop covers the slit and the other sits above it, so that it holds nicely in place. This will prevent the Brummel hooks coming undone. A very simple, effective and cheap solution which Flybubble Carlo devised after trying various ideas. The best solution we've found for this so far however are our Flybubble Brummel Covers.

More Information
Condition New
Shipping Details When in stock, UK approx 2-5 workdays, other countries see shipping page
Model Status Current model