You will find the serial number of your SCHMOLKE Carbon product on the invoice or on the delivery note for your order. If you no longer have the invoice at hand or if you bought your product from a retailer, you can find the serial number as follows: Frame: Underside bottom bracket and in bottom bracket Road handlebars/Gravel handlebars: Inside at both ends (R0000) MTB handlebars: Inside at both ends (M0000) Triathlon handlebars: Inside, lower end Stem: inside, visible when front plate is removed Wheelset: In the rim base (Ex.: L00010000) Rims: In the rim base (ex.: Road: MCID0000 and MTB/Gravel: 29GXG0000) Seatpost: Inside lower end (ex.: SR0000/SM0000) Saddle: underside (0000) There are no serial numbers on small parts and supplies.