Comment by aidenn0

TFA has a link to the amazon page for the bearing used. It's a bearing plus freewheel clutch. Most commonly (and in this specific case) it means sprag clutch[1], but it may be e.g. a ratchet/pawl[2] (like most bikes have) or a roller freewheel[3].

1: https://en.wikipedia.org/wiki/Sprag_clutch

2: https://en.wikipedia.org/wiki/Ratchet_(device)

3: Couldn't find a wikipedia page for this, so https://www.youtube.com/watch?v=AU4OguQmyMM