Includes: 2 frames, 4 axles, 4 bearing spacers, and 8 wheel spacers. All you need is bearings and wheels of your choice. If you want to make a custom racing model using inline racing wheels from your garage or Ebay, this is what you need to get started. Most inline skate wheels have the standard size 608 hub (verses the 688 micros) which fit the common size 608 bearings.