What is the purpose of the two head nails -- for flooring?

They are called duplex nails. They are designed for concrete form building. They are not coated with anything so they are easily removed. The first head contacts the surface and holds the form, stake or brace. The second head is to remove the nail.What is the purpose of the two head nails -- for flooring?
GREAT ANSWER f100! The only thing you left out is that they are called duplex nails.What is the purpose of the two head nails -- for flooring?
They are used for temporary bracing.


They have 2 heads so the top head can be easily


grabbed by a claw hammer.
the double headed nail is designed to allow it to be nailed down tight for holding purposes and still easily removed.





It's primary use is for temporary bracing that will be taken off at some point.
we use them form our steel pins for setting concrete forms.