Prevent prying eyes: This one-way mirror film protects privacy during the day: the stronger light side will produce a mirror effect. The other side will be transparent, this allows you to see outside without being seen. Protect from heat: Its reflective power (reduce the heat from windows). This one way mirror can anti 99% of UV and cut 85% of heat. It protects the skin against damage caused by UV rays. Penetrating daylight: Small loss of luminosity but clearly noticeable temperature difference and prevents prying eyes from the outside. Easy to install: This one-way film is not sticky after spraying with clean water and easier to install than adhesive film. After the water is dry, the viscosity is restored and is stronger than glueless films. Different effect between day and night: When indoor light is stronger than outdoor light at at night, people outside can see people inside. Don't forget to draw the curtain at night.