A magnetic clamp was a piece of technology used to magnetically adhere non-magnetic objects to a metallic surface.
A trio of royal guards stationed aboard the Chimaera utilized modified Force pikes with magnetic clamps to subdue Ezra Bridger. Their weapons emitted a yellow field capable of lifting and immobilizing Ezra, albeit it took all three pikes to subdue him, something he took advantage of when he hurled several boulders and rocks from a stolen piece of the Lothal Jedi Temple at his attackers to disrupt them. The boots of Darth Vader's armor featured magnetic clamps, which were utilized during his raid on Cylo's research base, when he breached a section of its hull, blowing the surrounding crew out into the vacuum of space.