1. The scissors all passed rigorous test when out of factory, screw is in the best position so don't attempt to tension it if
2. Don't use the scissor to cut air (cut nothing) often.
3. While using the scissor, must not push the moving scissor with your thumb.(refer to the pictures below)
4. Avoid falling, throwing it from high,because it damages scissor badly.
5. Clean the scissor after use it.