Package comes with two pieces of rim tape for use with the Zipp clinchers. Woven nylon material. Tape is extra thin with a thickness of 0.5 mm. Note: For Zipp 700c and 650c aluminum/carbon hybrid clichers, use the 16 mm rim tape. For Zipp 30 wheel set use 18mm but for the wider Firecrest and Firestrike carbon clinchers use the 20mm x 1/2mm rim tape.