Why not use a separate heating element?
The front panel's temperature is unstable, easily causing the flex cable to bulge. The heating plate provides even and uniform heat, like giving the phone a warm compress.
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seen from China

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seen from Australia
seen from United States

seen from Malaysia
seen from United States
seen from China
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seen from Germany
seen from Canada
seen from United States

seen from Philippines
seen from India
Why not use a separate heating element?
The front panel's temperature is unstable, easily causing the flex cable to bulge. The heating plate provides even and uniform heat, like giving the phone a warm compress.
Will heating damage the screen?
The temperature is controlled and only softens the adhesive; it won't damage the polarizer or LCD.
Samsung S4 Punching Pad 2 Layer Pad Red Mat or Foam Pad For Mobile Phone Lcd Oca Puching Pad