Here is a smart wearable device that keeps you warm and cold depending on your need. The POLAR SEAL GEMM has 3 power levels for cooling and heating down to 50F and 108F respectively. It has a compact design and can easily fit under your shirt. It lasts up to 7 hours on battery life.
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GEMM comes with gold plated magnetic connectors. It has a stealth mode in which its lighting is dimmed, so you can easily wear it under your shirt. You can change mode with the flip of a switch.
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