14x25.4x6 Swiss Nitro rc engine bearing ( Ceramic )
 
Fits many different brands including OS Engines-PICCO-REDS-TRITON--FX engines-LRP-Dyanmite-SH engines-ProteK-BLOK- and more. 
This is a high end Italian Swiss made bearing. 
 
Ceramic Balls
Highest quality available exceeds RC engine manufacturers specs
Low friction polymite bearing cage for ultra smooth operation
ABEC 7 rating