7.6 sizes of reusable blade for your option: Miller 0 for neonate,Mac 1 for pediatric,Mac 2 for small adult,Mac 3 for adult,Mac 4 for big adult, D blade for difficult airway. 5. With a fully charged battery,continuous operating time:140min. 1.The reusable blades are made of medical grade alloy,which is strong, durable and reliable. 2.Traditional laryngoscope blade can be easily converted to a direct laryngoscope 3.Water Resistance: IPX7 for the sealed blades with a “Sealing Cap”, which can be soaked in the disinfectant solution for disinfection; Often Saturdays, Sundays, and major holidays are not included in transit time estimates. We Strive for 100%Customer Satisfaction and we love to leave positive feedback's for our buyers. So, we request you to contact us and give us a chance.