Societa Industria Elettroniche (SIEL) MK 900 MIDI Synthesizer

via this auction

Note the handle in the second shot. "This is a professionally owned and used Societa Industria Elettroniche (SIEL) MK 900 MIDI Synthesizer - GMI that was purchased in the mid 80's, and then stored in a controlled climate studio for many years. The SIEL MK 900 was made in ITALY for only three years from 1985-1988. This model is equiped with, 61 key's, 10 voices, midi in/out, usb sounds, 2 outputs, and piano samples."

MK-900 SN 104746