Product Description: 3D pen filament refills is a biodegradable plant material, harmless and safe for children, very comfortable and environmentally friendly to use at home or in the classroom. Premium materials keep it printing smooth at all times, New eco-friendly 3D printing material is the best choice for adults and children to create in 3D The value-for-money large set allows children to fully develop their creative imagination and can also play a good protective role. .
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