These are basic USB UARTs which can achieve 115200 baud.

The device does not contain a well known USB UART bridge but is comprised of a Philips PDIUSBD12, Philips 87C52 and a MAX232 clone.

In Linux, the reverse engineered driver is imperfect and it's not possible to recommend this device for normal usage but it's a candidate for for testing unreliable serial connections.