Since our first manufactured singlemode zirconia ferrule in 1980, we have always taken into consideration our end user's comments and suggestions, and continued to improve our products. Although the zirconia ferrules appear to be just a simple ceramic cylinder, the outer diameter (OD) of the ferrules is grinded and polished at a controlled submicron level. Moreover, the dimensions of the ferrules need to be precise with a tolerance level of �}0.0005 mm, which is the requirement for a singlemode type ferrule. The ferrules have a precise hair-thin Inner Diameter (ID) for aligning the optical fiber with various ODs. The ferrule's ID is polished to a diameter of 0.001mm or larger than the OD of the optical fiber. Moreover, this ID has a precision of 0.001mm in concentricity and 0.0005mm in eccentricity for the singlemode ferrules used for optical communication components.