Help with removing the hub cap

Hi Everyone,
I am in the process of assembling a Harbor Freight 4x8 trailer and need help with getting the tiny hub caps off to mount the wheels. Are those suppose to be twist off type? I would like to confirm before applying more force.
Thx.
Peter
I am in the process of assembling a Harbor Freight 4x8 trailer and need help with getting the tiny hub caps off to mount the wheels. Are those suppose to be twist off type? I would like to confirm before applying more force.

Thx.
Peter