The accuracy of ZXZC deep groove ball bearings (Mechanical Bearing 607) are divided into four grades of tolerances with national standard GB/T307. 1 which compared with the ISO and AFBMA standard.etc is in the following table.
bore dimension: 7mm
Outer diameter dimension: 19mm
Radius rsmin: 0.3mm
Details at https://www.cnzxzc.com/product/60-series/mechanical-bearing-607.html
Manufacturer: Ningbo Hardchn bearing Co., Ltd