Tudor T601 (ETA 2824 base)

Tudor's earlier ETA-based caliber used before the brand transitioned to in-house manufacture movements. Based on the workhorse ETA 2824, the T601 received Tudor-specific modifications and quality control. Now largely superseded by the MT5400 series in current production, it remains found in older Black Bay and Heritage models and benefits from the ETA 2824's decades of proven reliability and easy serviceability.