Brompton / Sturmey Archer rear wheel circlip
Circlip - a combination of circle and clip
The circlip is also known as C-clip, Seeger ring, snap ring and Jesus clip
In the Brompton world, a circlip is used to hold the sprocket(s) / cog(s) on the rear wheel - a simple but good solution as no special tools are required to remove the sprocket stack other than a small flat head/blade screwdriver
The circlip is stretched around the driver (the part of the hub to which the sprockets slide onto) and sits in a groove - holding the sprocket(s) and (maybe) spacer(s) in place
As used on the following Sturmey Archer rear wheels:
Brompton Sturmey Archer BWR - 3 / 6 speed
Brompton Sturmey Archer BSR - 3 speed
Brompton single / two speed rear wheel
Brompton Sturmey Archer SRF3 rear wheel

Here is a short video to show how the circlip (and sprocket stack) is removed
Brompton Q part code: QRSPRCLIP
Brompton part number: 9024087
Sturmey Archer reference: HSL721
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