Static Lab Freezers (manual defrost)
These lab freezers all have a static refrigeration system. The primary benefit to this is that they can maintain a very tight temperature range, making them the best choice for very temperature-sensitive products. A secondary benefit is that because these laboratory freezers aren't circulating a lot of air with a fan, products like agar won't dry out as much.
The downside to a static lab freezer is that it must be manually defrosted. How often the freezer must be defrosted will depend on how often the door is opened and how humid the lab is. For products that can handle intermittent rises of temperature, a lab freezer with automatic defrost is a better option.