The CST 9x2" tube is ideal for makes/models such as:
Bolzzen Commando 4818, which is the entry level model of the two TNE (Teverun) blue/black coloured models. It has 600w motors with 6" rim with factory fitted 9x3.00-6 tyre (see notes). Use 90 degree variant.
Dualtron Popular, split rim variants of Dualtron Mini and Togo.
These models adopt a 6.1" rim. The Dualtron Popular introduced an 70/50-6.1 tyre (2.75" wide, near 9" diameter) which is typically retrofitted to Dualtron Mini in lieu of the original Dualtron Branded CST 8.5x2 tyre. This tube suits both of those tyres. Use 90 degree valve in the rear motor hub, 45 in the motor-less front.
Makes/models that adopt CST 230x50 tyres, such as Xiaomi MiI3/MI3Lite/MI44.
Progressively being adapted for application in 8.5x2 tyres (see notes).
Choice of 45 and 90 degree bend, 80 degree tilt. The 45 presents more like 60 degree.
Notes:
This tube presents similar to the CST 8.5x2" tube and has started to be offered in leu of 8.5x2 nameplate branded product, suggesting it is universal for 8.5" and 9" tyres on both 6.0" and 6.1" rims, including the common 8.5x2 "Xiaomi M365" tyres.
Regarding Bolzzen Commando, (blue/black TNE models) with 4818 model (2x600w motors) using a 9x3.00-6 tyre this tube is a much better option than 10x2-2.5" tubes. Also suitable for use with CST 9x2.50-6 Road Tyre [CM560] which is considered a better tyre than the stock 9x3.00-6. This tube can be also fitted with 10" tyres can be fitted with fender spacers similar to the TurboTight NAMI Klima Fender Spacer Kit. The Elite model (4823.4 with 2x1000w motors) has factory fitted 10" tyres due to presence of factory fitted fender spacers as shown below:
For motor hubs typically 90 degree is adopted, non-motor hubs 45 degree.