If you mean the Leupold magnetic bore sighter that has been around a while, yes.
I have one and find it quite useful. I have a tendency to swap scopes around between rifles. Once I have a load sighted in I put the boresighter on and document where the crosshairs line up. Then I have found I can move scopes around as needed, move the crosshairs where needed and I am usually within an inch on the first shot. It can also be handy if you travel, bump or drop your rifle and suspect optics issues. Put the boresighter on and check your notes.
This is a very small, handy and realtively inexpensive tool I sure would reccomend one. Mine has payed for itself many times over in ammo costs.