Multi Gauge Roller Bearing SetMulti Gauge Roller Bearings, Set of 4pc. This set comes with four sizes of insulator plates that can be changed with ease. The set will allow you to use the roller bearings with "S", "O", Standard" and "G" gauge equipment Our roller bearings are very easy to use You simply place them on the track (spaced ready for your locomotive). Incredibly versatile, they help with running in, testing and evaluation of locomotive performance, active cleaning of