It is constructed so that the only parts that can be changed in the field are the guides. It comes with three guides: the Flush guide, the Mill guide, and the Lip guide.
I do not recommend the magnet as a first choice in any fishing job. Even though the magnet is strong enough to carry the type of fish it is designed for, the fish itself is so often broken up or is of such a very irregular shape that you cannot get the magnet on a large enough area to realize the full effect of the magnet.
The fish and other circumstances will determine the use of several guides. You will have to determine on a job that you think will best suit the situation at hand.
Run the magnet within five or six feet of the fish and start circulating with as much pressure as possible. Lower the magnet to the fish, then pick up five or six feet and repeat this until you are sure the bottom of the hole is clean. Reduce the pump pressure and lower the magnet to the fish with a minimum of weight, and if necessary, rotate to move the junk, but always keep rotation to a minimum.