use of "per"

[manky]

Hi,from Japan.
The object has a size of 10 square meters and a weight of 50 kilograms.
I want to change the sensence using "per".

"The object has a weight of 1 kilogram per a size of 0.2 square meters."
Is this sentence is grammatically correct and narural?

[hobbes]

Gramatically correct, but not what I'd naturally say.

"The object has a weight of 1 kilogram per 0.2 square metres" or

"The object is 1 kilogram per 0.2 square metres"

as kilogram & metre already define the values as being weight and size. (A bit like "a male boy" for example)

[Touchwood]

Hi,

as an engineer, and being very pedantic, kilogram is a measure of mass, not weight!

Mike

[manky]

I work as a patent enginner so what you said is important for me.
Thank you!

[manky]

(A bit like "a male boy" for example)

This example is very easy to understand! Thank you