Double sided, clamps itself and your work.

This clamp will hold itself down, then it will clamp your workpiece.
Now you can use your Vac-Clamp whenever you want wherever you want.
A VC5 kit contains:-
One VC5 clamp.
Air supply tube with a 1/4″ pneumatic connection.3 piece spare seal/gasket set.
Instruction book.Link to Instruction Book

What are the advantages?
The VC5 has two vacuum generators built into the clamp body, one for each side. This means that the clamp will hold itself down on a flat non porous surface, and clamp your workpiece. Naturally enough it will work at any angle
Ambient air pressure is the clamping force. Air pressure at sea level is about 1kg per square centimetre (about 14.7 psi). So a clamp using the full face can exert a holding force of up to 150kg (330lbs). Smaller areas will give less clamping force
What if I am...
At higher altitudes air pressure is less which means the holding force of a vacuum clamp reduces with altitude.If you intend to work at the summit of Mount Everest (8,854metres, 29,028ft) the holding force will be reduced from 150kg (330lbs) to 50kg force (110lbs)