Magnetic Socket InsertsPart No. 521 • Magnetic insert firmly holds the fastener in the socket for easy installation and/or removal • Prevents fasteners from dropping into restricted areas where they can be difficult to locate and/or retrieve. • Magnetic insert can be left in or removed for use in other sockets. Includes 10 pieces: 10, 11, 12, 13, 14, 15, 16, 17, 18 and 19mmProduct Code:JS- AE521