Function Introduction

Balance the pressure difference

During the use of the heatstroke prevention wristband, due to factors such as temperature changes or altitude variations, there may be a pressure difference between the inside and the outside.

To balance this pressure difference, ensure the normal operation of the wristband, and avoid damage to the internal components caused by pressure issues, a pressure balance hole is usually provided.

Waterproof test

Meanwhile, to prevent water from entering the interior of the wristband through this hole, a one-way breathable membrane is attached to the back of the hole, allowing gas to be expelled from the inside to balance the air pressure but blocking external water from entering the wristband.

During the production process, the waterproof performance of the wristband is detected by extracting air from this hole. If the air cannot be extracted, it indicates good sealing and the waterproof performance passes the test.