Supplied in the excellent Challenge brand. Available in 2RS (Rubber Sealed), Open (Non Sealed) & ZZ (Metal Shielded). All our C3 bearings are boxed. The C3 refers to greater radial clearance to allow for high speed environments where excess heat is generated. Generally C3 bearings are used in engine and gearbox environments. You should always replace a C3 bearing with another C3 bearing, and on the same basis avoid fitting a C3 when not called for. C3 Bearings feel loose in normal ambient temperatures prior to fitting, and will show axial play until running at operating temperature. Sizes range from 6300 - 6309, other sizes may also be available but may not be displayed please contact us if you require a size not displayed on our shop.