Avoid TTRacing at all cost. After 2 years of use, you can see what happened to my TTRacing Swift X.
The material is really inferior compared to other brands. The same material used in the armrest also started peeling off.
No response from the customer service, even though I called and filed multiple tickets to their customer service.
Really pissed off and considering submitting an official complaint to KPDNHEP

I think it's the material, the other chairs I have - a Steelcase and an IKEA chair, don't have such issue.
Although a bit aged, the material doesn't just peeled off/break like the TTRacing.

At least they replied to you, haha. Mine ticket filed but no reply. Called them they said will reply to the ticket with 3 working days yadda yadda but after more than 3 weeks also no update.
My first and last purchase with them.