I will not describe the characteristics, already well described by Kiss Kool.
I have since 2005, bought on sale in a hyper market for 128Euros.
easy to use, the sounds are nice: casio ZPI technology.
I have criticized him in this small CTK, no pitch bend wheel, no audio output line, it's embarrassing to have to go through the headphone output for connection to mixer.
But it is an entry-level keyboard, you can take in light mop, hotel etc..
I bought its big brother the CASIO WK 3800 (for a pittance price also very cheap), ZPI same technology, but with separate audio output, no noon, USB, SD card slot and 76 notes.