HP USB Optical 3 Button Mouse DY651A. HP Part number: 361781-008 or 361781-006. HP Model number: M-U0013 or M-U0043-O. HP Spares part numbers: 395736-001 or 573077-001. CJE have, over the years, developed many of our own products for Acorn/RISC OS & Raspberry Pi computers.
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