The magnitude of a force vector has units of Newton.
Since the direction is "unit less", removing the direction aspect of the vector just subtracts a "unit less" unit, still leaving Newton.
You might say "apply a force of 5 Newtons to a rod" and someone should properly ask, "but what is the direction of the force?". And you might reply "apply a force of 5 Newtons perpendicular to the rod." But the units of the vector is just the units of the magnitude (but the vector has a qualification by including the direction).