This Aftermarket On-Off Toggle Switch (Optional Lock) replaces Delta 489105-00, Ryobi/Ridgid 46023. It is mainly used on table saws as well as numerous other bench top tools. This part replaces discontinued part #: 400060680002, 400060680002 and 1343759.Switches are commonly replaced parts in power tools. A switch handles all on/off and variable speed functions. They also have a role in electric breaking; they can momentarily reverse electrical polarity. Because switches use mechanical internals, they tend to degrade and wear out over time, eventually requiring replacement.