This is a heat-retaining hot water bottle that doesn't require water changes. Operation has been confirmed. Hot water bottle use: Approximately 6-8 hours Hand warmer use: Approximately 3-5 hours Size: Approximately 170cm x 245cm x 50cm (width x depth x height) Weight: Approximately 1000g Thank you for viewing. First come, first served! Instant purchase OK! The items in the photos are all included. ★ Returns and refunds due to personal reasons are not accepted. 　Please be aware of this beforehand. A005418