The Magfence II® from Carter Products is a band saw rip fence magnets that switch on and off and allow for easy attachment to most ferrous metal tables. You can move the 30mm magnets inward and outward to fit the table size required, and switch them off when you’re done. The basic Magfence II is 15″ long and 3″ high, with accessory add-ons available for resawing. It’s priced at $99.95.