Seat Post Shims

Please find below links bike seat post shims for the specified dimensions. 27.2mm is the base post size (there are other sizes) for the most popular Bikase BumpStop Suspension Seat Post 

27.2mm (ID) - 30.4mm (OD)

27.2mm (ID) - 33.9mm (OD)

27.2mm (ID) - 31.8mm (OD)

31.6mm (ID) - 34.9mm (OD)