The D4 is a fully professional Drum and Percussion sound module.
It features 500 drums sounds, sampled at 48kHz and stored on an internal ROM chip, from great acoustic drum types to electronic drum sounds. Orchestral and ethnic percussion sounds and various percussive effects are also available. There are 21 programmable drum kits as well as full 16-channel MIDI implementation.
The D4 has 12 trigger inputs allowing its sounds to be triggered by acoustic sources or MIDI pads. A hi-hat pedal jack allows use of a footswitch to create more realistic hi-hat effects. There are also 4 independent outputs for either 4 mono outs or 2 stereo outs.
Here is a link to the full product reference manual >>ALESIS D4<<
All in good working condition