Instruct: Classify a given review into positive or negative sentiment.
Query: MEASURE YOUR SEATPOST CLAMP BEFORE YOU BUY

The rails on this saddle are approximately 54-55 millimeters apart, measured from outside edge to outside edge. My aluminum seatpost clamps, the single bolt aluminum "sandwich" type clamp common on many if not most average-priced seatposts, have rail grooves that are no more than 50 millimeters apart, outside edge to outside edge.The rails and the grooves have the same diameter; diameter is not the issue. The rails are just too far apart for both of them to sit in both grooves of the clamp simultaneously, and they can't be made to fit.So, to avoid disappointment, and the unnecessary expenditure of time and money, I'd recommend that you measure the relevant dimensions of your seatpost clamp before you make your purchase decision.