Power Supply: AC 100 V (50/60 Hz); Rated Power Consumption: 400 W; Heat Storage Temperature: Approx. 156°F (65°C); Heat Storage Time: Approx. 10 minutes (when at room temperature of 66°F (20°C)); *Heat storage time varies depending on the ambient temperature. Electricity bill (per heat): Approx. 2.1 yen *Calculated based on an estimated unit price of 31 yen / kWh; Continuous usage time: Approx. 8 hours (use in futon) / For kairo purpose (use on the body) approx. 4 hours *Usage time varies depending on the ambient temperature. Repeated Use: Approx. 500 times (approx. 2 years); Cord length: 35.4 inches (90 cm); Safety device: Temperature fuse, power shut-off switch, thermostat ; Set includes: Hot water bottle, thermal cover, heat storage power cord set, instruction manual (English language not guaranteed) ● Keep your desk work in winter with energy saving and cute warmth.