Yes the magnet is rated at having 500 lb pull (i don't know the term) capacity. It's about 2.5" in diameter and maybe half inch thick. Just approximating.

I have not yet gotten to measuring the magnetic field. The problem is, the cancer is inside my head so really a question of what the field is where the tumor is. I estimate it's 1 to 1.5" beyond the inner diameter of my skull near the back. So if my skull is half inch thick it's 1.5 to 2" I have to reach. I have no idea if I have the magnetic strength so for now I am just guessing.