The -40°C Medical Freezer is Made of high density non-fluorinated polyurethane foam insulation. Independent inner door to avoid more cooling leaking out, and provide more stable inside temperature performance. The standard is equipped with a 25mm test hole.The wide voltage band is 187V~242V. With power failure protection, the startup delay feature protects the device from damage. The door lock is designed to prevent abnormal doors from opening. Equipped with a large screen for easy viewing Standard test hole.