Find all vertices in a radius around a center vertex

I am trying to find all vertices within a certain radius around a center vertex. Then setting these vertices alpha to 0. I am currently using this code:

public void clearFog(Vector3 center, float radius)
		colours = mesh.colors;
		//find the point in local space
		Vector3 localSpaceCenter = transform.InverseTransformPoint(center);
		for(int index = 0; index < verts.Length; index ++)
			float distance = Vector3.Distance(verts[index], localSpaceCenter);
			//if vert is within the radius 
			if(distance < radius)
				colours[index].a = 0;

		mesh.colors = colours;

But i clearly don’t understand something here, distance is always returning values between 1 and around 1.006 ish… how can the distance of every vertex in the mesh be between 1 and 1.006 away from the center vertex? It makes trying to judge how large the radius should be very difficult. What am i doing wrong here?

Thanks in advance.

This has been solved, i think it was because of the use of localspace, getting rid of that and just using the hitpoint worked i believe.