The Yuanxing 10x2.125 is the factory stock tyre on Ninebot F & D Series (such as F20, F30, F40) and InMotion Climber & Air Series.
The CY-344 designation is factory stock on InMotion Cruiser (44PSI). Ninebot's original is CY-327 designation (50PSI) which was embossed with an orange/grey label.
Designed to accommodate 7" rims, detailed list of common models include:
Ninebot Segway F series such as F20, F20A, F25, F30, F30A, F40, F40A, F2, F2 Pro & F2 Plus
Ninebot Segway D series such as D18E, D28E & D38E.
InMotion Climber (AKA Commuter Climber), Air and Air Pro (noting the Air Pro rear is a factory solid).
Typical weight 550 grams.
Nameplate tyre pressure: 44PSI.
Width at bead: 44mm.
Tube type.
Yuanxing branded. Some production batches have a white line.
Notes:
This is the most common (if not the only) aftermarket tyre on market and produced by the same manufacturer as the original Ninebot tyre designation CY-325 and commonly adopted as the tyre of choice to renew in these makes/models. The only observed difference being the lower tyre pressure.
Typically paired with 10x2.125 tube, Cruiser adopts straight valve.
InMotion Climber is marketed as InMotion Commuter Climber in Australia through Scooter Hut. A 60/70-7.0 size tyre is observed fitted on the InMotion Global Air Pro disassembly video.