Clamps

What are the differences between a cardellini and mafer clamp?  What are 2 different uses for them on set?  If you had to ask someone to go grab a cardellini clamp out of a box, how would you describe it to them?

    The differences between a cardellini and a mafer clamp are that mafer clamps don't close fully and are stronger. Two different uses for them on set are using a cardellini to clamp onto a flat surface and a mafer to clamp onto round or rough surfaces. If I needed to describe a cardellini clamp to someone, I would describe it as a clamp with a shaft that has a 4-way knob that can spin on it.