We present a case of an unexpected difficulty in ventilation following intubation for mastectomy. Difficulty in ventilation during GA was due to manufacturing defect of the endotracheal tube. Ventilation difficulty due to tube defects are rare, moreover it might be hard to detect this kind of a defect with routine evaluation. However, if the defect is not detected it would may cause catastrophic results. In our case the problem was carefully evaluated and solved uneventfully after following an algorithm.