I had to purchase a replacement as my seat and seat post was stolen. Easy to install.
Despite saying on the Decathlon site and being told instore that this will fit the Rockrider 520 it is too small. Unfortunately my grandson has bent it out of shape trying to fit so I will now have to pay out for a larger one. Very unhappy with this situation and it has put me off using Decathlon for spare parts.
I'm very sorry to read that you were misinformed regarding the diameter and suitability of this seat clamp.
Please return it to us for a refund at your earliest convenience and I will work with the b'Twin brand to make sure that the information provided on the website is accurate.
Peter Lazarus, National Cycling Manager, DECATHLON
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