Hi Abel, these requirements must be met when installing tinted films on windscreens and windows:

- They must be non-reflective

- At least 70% of light must be able to pass through the front windscreen and the two front side windows

- At least 25% of light must be able to pass through the rear windscreen and the two rear side windows

- The front windscreen must not affect the transmission of signals between the In-vehicle Unit (IU) and the Electronic Road Pricing (ERP) gantry

You can find out more here: https://www.motorist.sg/article/216/6-reasons-to-tint-your-car-windows