These are very small clamps. They will not serve the purpose if you are using 18mm plywood. There are 3 clamps in the set. Big, Medium and Small clamps. Medium and Small clamps are completely useless as they are very small. Big one can be used with plywood but it is not strong enough to hold the wood properly.
I don't recommend this for wood work. If you are using this with 6 mm plywood, then you can buy.
These are not for professional use but Home use. The C column is of good finish and material. But the turning lever is not fine. they should have terminated the nail with a round tip. Its okay for small work.
Too small to hold jobs securely, the smallest one is just showpiece without any practical use. Those jaws tend to put mark on wood if clamped too tight unlike my taparia 3" & Ketsy 5" clamps. Go for a bigger clamp