As displayed on the Website information it says that 28.6 mm clamp will fit a 27.2 mm seat post . So I did the same by visiting the nearest Decathlon store at Ghatkopar Mumbai. Bought one and kept it as a spare in my Saddle bag . Had an emergency where my original seat post clamp malfunctioned . However when I tried the seat post clamp taken from Decathlon it didn't fit . I unscrewed the Bolt all the way open and tried to install it still it didn't fit. When I placed the btwin seat post clamp over my Old seat post clamp for reference and measurement ,I was shocked to see that the clamp was way too small for by bicycle frame ( please note my Seat post is 27.2mm ) was totally disappointed with this product due to incorrect information provided on the website . when I check on Google it said for a 27.2 mm seat post It would need a 31.8mm clamp. Worst part is one of the Store guy also suggested me the same seat post clamp i.e is 28.6mm. please suggest me what should I do. I have the seat post clamp totally untouched stored in my Saddle bag however I do not have the original package of the clamp but I do have the original bill provided during the purchase.
Thank you for taking the time to give us your review. We are really sorry for the experience you have had with the seat clamp. The Information for the product is common globally and if this is wrong it is a big problem. Please give me time to check for the accuracy in dimensions at the store. I would also like to know which bike you are using to know if the problem is bike specific. However as a solution to you you can return the product at the store purchased stating the above reason and the store will be able to give you the best solution (replacement/refund) based on better understanding the problem. Thank you.