Pro:
That definitely too short rope can be thanks to the guidance wonderful against a loose twice as long switch (max. 3mm diameter, z. B. from Gepotec). I have chosen here for a reflective variant because the black is too easily overlooked. The overall construction is dibasic.
Contraindications:
My seatpost is too thin for this great device. Even with the supplied plastic covers as distance adjustment is there still too much leeway. Accordingly it is necessary to find a solution themselves.
Conclusion: Recommended if you is a little extra work to invest willing.