This item is new and has only been used once. It's a free-size cool vest with 5-point cooling and heating functions, offering instant cooling to -28°C and instant heating to 39°C. - Model: PRO model - Cooling Temperature: Instant cooling to -28°C - Heating Temperature: Instant heating to 39°C - Battery Capacity: 20,000mAh - Cooling/Heating Functions: 5-point cooling and heating - Size: Free size Thank you for viewing.