Cosy Joe Rechargeable Hot Water Bottle Blue. Soothes & Comforts. Rechargeable hot water bottle Ideal for use as a hand warmer or as a heating pad for soothing body aches and pains.. Permanently sealed so no risk of scalding and no water required. Simply get cosy. Lasts up to 8 hours. Ready in 10-15 minutes. No refilling. Suitable for 5+ years. Rechargeable hot water bottles