Feature(may vary by option.)

●Size: M
●Approximate neck circumference: 10.2 - 13.4 inches (26 - 34
●Color: Blue
●Materials: TPU (Thermoplastic Polyurethane), PCM (Phase Change Material), Normal Paraffin (Octadecan)

[S size]

Description

Maintains cold temperatures and maintains approximately 86°F (27°C).
Lasts approximately 60-120 minutes.
You can use it by simply cooling it in the refrigerator for about 10 minutes and using tap water for about 30 minutes.
Prevents frostbites from being too cold.
No water droplets.
Can be used permanently.