These are FULL ceramic bearings that I got a factory to make but they could not withstand the impact from street skating so that makes them ONLY SUITABLE FOR LONGBOARDS.

The balls are Silcon Nitride and the races are Zirconia.These are the best bearings you can buy for your longboard, you can read more HERE

Note: These are not the typical "ceramic bearings" that you can purchase from skate brands, those are actually ceramic HYBRIDS, only the balls are ceramic the races are still the same old chrome steel. If you want ceramic hybrids, check the BEARINGS category on the left. LSP has also gone direct to the factories and can therefore sell those at a fraction of the price you would typically pay for branded ones.