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TI 561 11Model: TI-561-11 (TI-500 prototype)Code: Ok
Battery:
  309
WCase: black plastic WBand: rubber matching bracelet Face: blue frame 
Manual: Yes Box: No  Lamp: bulb
Year: 1980 Price: xxxx
Function: The watch has six functions- hours, minutes, seconds, month , date and light
Info: prototype created in the Rieti laboratories, for possible productions, red and green buttons, 
the same model with the writing TI-500  TI-561-11