Check the listing for details. OS 61 FX/AX Stainless Bearing set. Condition: New. Listed at 1.97 USD. Picture is for bearing type only Picture is for engine type only OS 61 FX/AX Stainless Bearing set Front Bearing: 6901ZZ 12 X 24 X 6 Premium Shielded Bearing Rear Bearing: S16003M 17 X 35 X 8 Stainless Steel Bearing with metallic retainer RCBearings OS high speed two stroke rc engine bearings offer dependable, long lasting smoothness. These have as good or better performance than what came standard in your engine at a fraction of the cost of OEM bearings! These have a high speed plastic retainer from Japan in the rear bearing. NOTE: These rc bearings are appropriate for Heli engines. All heli engines .40ci and above should use a rear bearing with a high speed plastic retainer! Beware of other sellers that try to pass off cheap standard bearings with metallic retainers for your expensive heli engine! Support Email if you dont know which bearings you need or if you are looking for a kit we dont already have.