Apple Watch biometrics include features like heart rate monitoring and wrist detection. The SYB Wrist Band blocks these features because it uses silver fibers that prevent the watch’s sensors from working through the shielded material.

What Are Apple Watch Biometrics?

Apple Watch includes several biometric sensors that track health and fitness by measuring your body’s signals. These typically include:

• Heart Rate Monitoring – uses photoplethysmography (light sensors) to detect blood flow

• Wrist Detection – detects skin contact to lock/unlock the device or trigger certain functions

• Blood Oxygen Sensing – uses red and infrared light to estimate oxygen saturation

• ECG (Electrocardiogram) – measures the electrical signals from your heart

• Skin Temperature and Other Sensors – in newer models

These sensors require direct skin contact to function properly.

Why Does the SYB Wrist Band Block These Biometrics?

The SYB Wrist Band is made with 90% silver thread, which acts like a Faraday cage—a barrier that blocks electromagnetic fields (EMF) from reaching your skin.

This shielding layer:

• Prevents EMF from penetrating your skin

• Also blocks the Apple Watch’s sensors from reading your biometrics

• As a result, features like heart rate, ECG, and wrist detection will not function while wearing the SYB Wrist Band

This isn’t a flaw—it’s intentional. The purpose of the SYB Wrist Band is to protect your body from EMF exposure, and that requires creating a barrier between the device and your skin.