WK-3300 and WK-3800
Main features:

• 76 touch-sensitive keys
• 166 rhythms
• SmartMedia™
• 32-voices polyphony
• 670 Tones
• 242 digital effects
• Pitch-Bend-Wheel
• General MIDI
• SD card slot
• USB MIDI

 
 
Further informations directly from Casio
http://music.casio.com