The Systemair VSR-300 has these fans:
[[https://www.haustechnikdialog.de/Forum/t/229492/Kugellagertausch-ebm-papst-K3G190-RC05-19?PostSort=1|German forum]]
[[https://www.youtube.com/watch?v=M1O--y3kg0o|Youtube instruction from Systemair]]