Using a computer without having a mouse is a difficult task. If you're looking for a mouse for your child, this one could work very well.
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Logitech M325 Wireless Mouse, 2.4 GHz with USB Unifying Receiver, 1000 DPI Optical Tracking, 18-Month Life Battery, PC / Mac / Laptop - Light Silver Grey
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Logitech M325 Wireless Mouse - Dark Silver
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LOGITECH Wireless Mouse M325
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Logitech M325 Wireless Mouse