VTech Crystal Sounds Mode D'emploi page 15

Technical Specifications:
Dry Materials
Wood, plaster, cardboard, glass
(without metal, wires or lead)
Brick, plywood
Reinforced concrete
Metal grills or bars
Metal or aluminium sheets
Note:
For wet and moist materials, the loss of range may be up to 100%.
Material
Thickness
< 12 inches
< 12 inches
< 12 inches
< 1/2 inch
< 1/2 inch
Loss of
Range
0-10%
5-35%
30-100%
90-100%
100%
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