1 x 1 1/8" Upper Bearing (TH873E). Also known as: MH-P03K, MR122, MR054 p03k TH873E, MR122, MR054, MR115, HSS20130K, PT-R401, AC3041 R2. 1 x 1.5" Lower Bearing (TH073). You will receive 1 x upper and 1 x lower bearing for an FSA headset.
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