100% Polyester Helmet Fan Attachment With Lithium Ion Battery (HB/NB) OSHA COMPLIANT The fan attachment sends air into the helmet to release heat and humidity build up in the helmet, at the same time providing cool sensational feeling in the head, as well as the the face and neck area. With the rechargeable lithium ion battery that is included in this package, you will not have to worry about changing batteries. On top of that, you'll get more airflow (250% more than the AA battery type) and 8 Hours of continual usage at the HIGH setting. Includes: Helmet Fan Helmet Strap MINI Rechargeable Lithium Ion Battery Belt Clip Cable Cord Band Rechargeable Lithium Ion Battery will come with 4 Power Levels, with up to 100% more airflow, and longer battery life. Attachable to any standard baseball cap style Hard Hat/Helmet, powered by Rechargeable Lithium Ion Battery. Does not come with Hard Hat Additional Details ------------------------------ Product description: 100% Polyester Helmet Fan Attachment With Lithium Ion Battery (HB/NB) OSHA COMPLIANT The fan attachment sends air into the helmet to release heat and humidity build up in the helmet, at the same time providing cool sensational feeling in the head, as well as the the face and neck area. With the rechargeable lithium ion battery that is included in this package, you will not have to worry about changing batteries. On top of that, you'll get more airflow (250% more than the AA battery type) and 8 Hours of continual usage at the HIGH setting. Includes: Helmet Fan Helmet Strap MINI Rechargeable Lithium Ion Battery Belt Clip Cable Cord Band Rechargeable Lithium Ion Battery will come with 4 Power Levels, with up to 100% more airflow, and longer battery life. Attachable to any standard baseball cap style Hard Hat/Helmet, powered by Rechargeable Lithium Ion Battery. Does not come with Hard Hat