Reed switches are available in three contact forms. Form A switch is a single-pole, single-throw, normally-open device. Form B switch is a single-pole, single-throw, normally-closed device. Form C switch is a single-pole, double-throw device. The choice between these contact forms will normally depend on the type of logic information desired or the type of load that is being switched in an application. Other key characteristics to consider when selecting a Reed Switch for an application include size, drop-out versus pull-in sensitivity ratings, expected switching loads and number of switching cycles, and mounting methods that could benefit from value-added cut and form processes. Reed Switches come in a wide range of sizes, ranging from 7mm up to 50mm in glass length. Additionally, various magnetic sensitivity ratings are available. It is also critical to know the voltage and current of the load being switched as well as the type of load being switched. Capacitive and inductive loads have different effects on the contacts of a Reed Switch compared to those of a resistive load.