Double side-scroll mouse device

A double side-scroll mouse device adapted to be operated by a thumb, an index finger and a middle finger of a user, said double side-scroll mouse device comprising:

• a housing unit has
• a lower casing that has a bottom face portion, an extension face portion disposed above, surrounding, and connected to said bottom face portion, a first lateral face portion disposed above and connected to said extension face portion, and a second lateral face portion disposed above and connected to said extension face portion, and spaced apart from said first lateral face portion in a left-right direction, and
• a casing side skirt that is connected to said lower casing, and that has a first operating wall portion extending upwardly from one of said first lateral face portion and said second lateral face portion of said lower casing, a second operating wall portion extending upwardly from an upper end of said first operating wall portion, and a palm supporting portion connected to said first operating wall portion and said second operating wall portion and cooperating with said first operating wall portion and said second operating wall portion to cover said lower casing;
• a main button unit including a first mouse button that is located above said housing unit and that is adapted for operation by the index finger, and a second mouse button that is located above said housing unit and that is adapted for operation by the middle finger;
• and
• a side scroll unit including a first scroll wheel member that is disposed on said first operating wall portion and that is rotatable about a first axis being perpendicular to the left-right direction, and a second scroll wheel member that is disposed on said second operating wall portion and that is rotatable about a second axis being perpendicular to the left-right direction and being substantially perpendicular to the first axis, said first and second scroll wheel members being adapted for operation by the thumb.