SuperGuardZ® Flexible [Anti Blue Light] Screen Protector For Samsung Galaxy A21   Exposure to electronic devices (e.g., smartphones and tablets) can cause eye strain, fatigue, pain, and even severe headaches as their screens release blue light. Moreover, it has been known that blue light exposure can also lower melatonin levels associated with deep sleep. SuperGuardZ® anti blue light screen protector is especially designed to filter blue light to eliminate its negative impact on your health. Features:           Reduce eye-fatigue and eye-strain: Filter harmful blue light and prevent it from impairing vision and ability to concentrate (especially for children)           Health Protection:  Promotes healthy melatonin levels for deep sleep           Highest Quality Optical-Grade PET film: Best material to protect your devices from scratches and high-impact drops                     Ultra Clear PET Film: 99% transparency for HD clarity           Real Touch Sensitivity: Natural feel that provides flawless touch screen accuracy           Bubble Free: Self-adhering surface to prevent bubble generation for easy installation           Oleophobic coating: Prevent fingerprints and other oil contaminants           UV Protection: Reduces eye strain caused by your screen           Pre-cut to fit your screen exactly Compatibility:           Samsung Galaxy A21 Package Content:           Premium Screen Protector           Wet/dry Clearing Wipes           Dust Remove Paper SuperGuardZ® Lifetime Warranty:           SuperGuardZ® fully stands behind our products with lifetime warrantys           SuperGuardZ® offers you a quick, no-hassle REPLACEMENT OR REFUND            SuperGuardZ® products are warranted against manufacturing defects (e.g., bubbles)