Headset Bearing TK518B ACB518K MR127 TH-073E 1 1/2'' 1.5 (B)

ACB518K, MR110, MR127, TH-073E MR110, ACB518K, TK518B. 1 x 1.5" Lower Bearing (TH073) for an FSA Orbit (No.57) Headset. ZS56 BOTTOM HEADSET BEARING. You will also need an upper bearing which is PO3K / TH873E / MR122.

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