Park SS-15C Single Speed Spanner & Bottle Opener. Park SS-15C Single Speed Spanner & Bottle Opener. Designed and built especially for single speed bikes. The SS-15 is a forged spanner w/ a 15mm socket wrench for axle nuts, 15mm open end wrench for pedals, tire lever, and bottle opener. Just the right size and length (17cm/7) to take along or to wrench in the garage. This is a great gift for any bicyclist !!