This is one of our most frequently asked questions: What is the difference between the Standard, Industrial, and Professional Twice as Sharp® Scissors Sharpener? The short answer is the honing wheel that is included with the machine.
Check out this video for more information:
You can compare the models here: https://www.wolffindustries.com/shop-by-industry/sharpening-systems/twice-as-sharp-landing.html
Standard Buffing Wheel: https://www.wolffindustries.com/standard-buffing-wheel.html
Industrial Honing Wheel: https://www.wolffindustries.com/industrial-honing-wheel.html
Professional Honing Wheel: https://www.wolffindustries.com/professional-honing-wheel.html