Heat Preservation Duration : 8-10 Hours Power : 50W & Under Brand Name : Sarmocare Origin : Mainland China Heating method : Aluminum heat sink type Product specifications : 12*8.5*4.5cm Power supply method : USB Product Category : Hand warmer Built-in battery capacity : 4000 mAh-8000 mAh Rated power : 10W Whether built-in battery : Yes Endurance : 8-12 hours Rated voltage : 5V Gross weight : 125g Hand warmer Product Name: digital hand warmer Product material: abs+ metal aluminum Input voltage: 5V Rated current; 2A Lithium battery capacity: 4000/8000mah Rated power: 5W Product size: 97*68*30mm Hand Warmer Redefine The Temperature In The Palm of Your Hand Warm The Whole Winter Power Bank Is Also A Hand Warmer A.3 Seconds To Heat Up B.Intelligent Temperature Control C.It`s Also A Power Bank D.Long Battery Life Three-speed Temperature Control 55 Warm All Day Long Battery Life It`s Warm and You Don't Need To Wait Low temperature range: 35-45 Medium temperature range: 47 - High temperature range: 55-60 This data is from the laboratory and is for reference only, The specific use depends on the ambient temperature Hand Warmer One Key Open Real-time See Temperature Smart Temperature Digital Screen Visualization Temperature Safe and Secure One key switch One key shift, 3-gear optional The screen displays the real-time temperature High capacity polymer battery brings power at critical moments