This portable visualizer is made of cardboard, so it is eco friendly and with triangular and modern shape, it's cheap to build. the system is easy to carry and transport in my school bag or by a teacher in his backpack. My portable visualizer is made of three parts, the first is very simple with the base on my visualizer, the second and the last part are retractable part from top to bottom. So it's very easy to use and cheap.
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