They are held down with with stick down material,no magnets.I have not used them yet.The long extensions,the holder is real easy to make.I made one out of aluminum for my 34" extension bars in 1/2 and 3/8 drive.Drill a couple holes for the extension bars and a hole to mount to the side of the toolbox.It did not cost me a dime for the aluminum,I had it on hand.Can make it out of steel or angle iron too.