id is 25mm od is 75mm. i got them off alibaba so i suspect they may not be genuine although they offered me a choice of genuine or generic. All the markings on the bearings and boxes look the same as images i found on various websites selling them. i do find it a little odd that German made bearings shipped from Taiwan but i guess there are lots of machine builders in Taiwan that may use them, i did see that quite a lot of industrial printers and embroidery machines use the same bearings as our machines. if they are fake they are very good fakes as i really cant tell the difference.
I measured them up with a micrometer and they are spot on dimension id, od and thickness. i have no way of measuring run out on the bench as they need a preload on them. i guess i could stick them in the machine and measure with a dial gauge but i'm not at the point of installing them yet. The lady i dealt with was very responsive and helpful, they shipped via dhl and it only took 2 weeks. it feels kinda sketchy sending a person in a foreign country money for something but i figured i could always get my credit card company to step in if the deal went sour.
here are the generic ones
https://xrtbearings.en.alibaba.com/p...479e43d4Adesxn
here are the ones they claim that are genuine.
https://xrtbearings.en.alibaba.com/p...479e43d4Adesxn