Ultra Clean Holdings, Inc. reaffirmed earnings guidance for the fourth quarter 2017. For the period, the company expects revenue to be at the high end of its guided range of $240.0 million to $250.0 million, with operating margins within the target range of 8% to 10%. The company provided earnings guidance for the first quarter 2018. For the period, the company expects revenue to increase as compared to the fourth quarter of fiscal 2017 and operating margins to remain generally consistent with the fourth quarter of fiscal 2017 and within the target range of 8% to 10%.