The FS1000A is basic RF transmitter than comes in at least two frequencies, 315 MHz and 433.92 MHz.

None of the devices tested are particularly well tuned and tuning also alters somewhat when attaching an antenna. The Gqrx image shown is one example FS1000A at 433.863 MHz with a 17cm antenna. On the same plot we can see a faint signal from another device which is exactly 433.92 MHz.