[Number of buttons] 8 (Including wheel button)[Size] LL size (width 114.7 mm x depth 181.9 mm x height 57.2 mm), ergonomics design, with lift rest[Power supply] AA alkaline battery or AA manganese battery or AA nickel hydrogen battery x 2[Sensor system] Optical sensor system[Weight] Approximately 260 g (without battery)[Ball size] diameter 52mm.
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