The NSA listed T-4 utilizes patented "Reverse Polarity" technology to produce a bi-directional field of at least 20,000 Gauss positive and 20,000 Gauss negative per cycle. This proprietary technology creates the highest flux field of any degausser available and ensures permanent erasure of the highest coercivity media available today. It is also projected to handle future media technology for years to come. Other degaussers may have either a positive or negative pulse, but not both; this technology is unique to the T-4. There is also no drawer to open and close, which reduces operator handling and increases efficiency.