All Ai refurbished Elite vacuum ovens have been fully tested to meet Ai performance standards before shipment. Unit may have minor cosmetic damage which will not affect its performance. All refurbished Elite vacuum ovens carry the same 2-year Ai warranty. The E44 ELITE series digital vacuum ovens feature our 5-side chamber jacket heating system that covers left, right, up, down and backside of the chamber; all metal internal vacuum tubing (compare to rubber hose) for better vacuum levels and durability; and build-in secondary over-temp dial for enhanced over temperature protection.These ovens can greatly reduce drying time by maintaining a consistent vacuum level within the chamber. Every one of our vacuum ovens goes through a 24-hour vacuum leak test, and is quality controlled in New Jersey or Nevada before leaving our warehouses. Attention: Before initial use, run oven at 400F without vacuum for 15 minutes to burn off any residue that may have been introduced during the manufacturing process. IMPORTANT! NEVER LEAVE YOUR OVEN UNATTENDED WHILE OPERATING. Across International is not responsible for any loss of material inside of the oven.