EZO

The bearing industry number is a standardized designation for a particular boundary dimension set. For EZO miniature bearings, numbers such as R1, R144, R155, R166, R2-5, R2-6, 1810, and 188 correspond to specific bore, outside diameter, and width combinations. The industry number does not by itself define shield type, lubrication, or tolerance class, so the full manufacturer part number should be used when ordering. For example, an EZO R166 with double shields and oil lubrication carries a different MPN than the same industry number with grease. 3G Electric lists both the industry number and the MPN to help buyers match the correct variant.

The EZO R144 has a 1/8 in bore, 1/4 in outside diameter, and 0.296 in flange diameter. The EZO R155 has a 5/32 in bore, 5/16 in outside diameter, and 0.359 in flange diameter. Both are extended inner ring flanged miniature ball bearings with double shields. The R144 is listed with grease lubrication in the 3G Electric catalog, while the R155 is also listed with grease. The larger R155 provides a slightly higher bore and outside diameter for applications where the R144 envelope is too small. Selection depends on shaft diameter, housing bore, and available axial space.

Yes. Several EZO miniature and flanged bearings in the 3G Electric catalog are supplied with oil lubrication. Examples include the R1 (1/16 in bore, 3/16 in OD), R166 (3/16 in bore, 3/8 in OD), 188 (1/4 in bore, 1/2 in OD), R2-5 (1/8 in bore, 5/16 in OD), and R2-6 (1/8 in bore, 3/8 in OD). Oil lubrication is often specified for lower starting torque or higher speed operation compared with grease. The MPN suffix typically indicates the lubricant type, so the full part number should be verified. 3G Electric lists lubrication type as a separate specification field for each SKU.

In EZO part numbering, ZZ generally indicates double metal shields, one on each side of the bearing. Shields are non-contact or low-contact closures that retain lubricant and reduce the entry of larger contaminants while adding minimal drag. They are not the same as sealed (2RS or similar) designs, which use contact seals and provide greater exclusion of fine particles and moisture but higher torque. Many EZO miniature bearings in the 3G Electric catalog use double shields, including the R144, R155, R166, R1, R2-5, R2-6, 1810, and 188. The complete MPN should be checked because additional suffixes define lubricant and tolerance.

Start with the shaft diameter to determine the required bore, then confirm the housing bore and available axial space to match the outside diameter and flange diameter. For EZO flanged bearings, the flange provides an axial locating surface, which can simplify housing design. Check the load direction and magnitude, speed, and operating temperature to choose between oil and grease lubrication and between shielded and open configurations. The extended inner ring version can ease mounting where the shaft shoulder is not precisely controlled. 3G Electric lists bore, outside diameter, flange diameter, shield type, and lubrication for each EZO SKU to support this selection process.

3G Electric provides bearing industry numbers and manufacturer part numbers for EZO products in its catalog. These identifiers can be used to cross-reference against existing drawings or competitor part numbers where the boundary dimensions and closure type match. However, cross-referencing should not rely on industry number alone, because shield type, lubrication, tolerance class, and internal clearance can differ between manufacturers and between variants from the same manufacturer. For critical applications, verify the full specification against the original bearing requirements. 3G Electric can assist with part number confirmation and availability checks for the 205 EZO SKUs currently listed.