This is a replacement magnet for the Rickenbacker 4001 bridge pickup. This is a blank and you will need to drill for the mounting screws as they varied on Ricks. It is the same rubberized ceramic material. It is drill-able and machine-able and cuts easily with a bandsaw if you want to modify it for another use. The magnet is marked North. Dimensions are  83mm L x 25mm W x 8.5mm H. It is charged through the 8.5mm direction.