1,Full range of type. 2,Ring With 154mm,172mm,200mm,230mm,254mm,300mm 3,Long life time 1 Drawing2 Size3 About our company and factory 4,QUALIFICATION CERTIFICATES5 We have pass the Alibaba Supplier Assessment by TUV,the report for you refer: http://hzsaiwei.en.alibaba.com/company_profile/trustpass_profile.html?certification_type=intl_assessment Shaded Pole Motor Part Ring