ATLAS SELECTOR This Selector is an Electrical Control Device Designed for Layouts of Any Scale by Atlas Model Railroad. FEATURES SPDT. This device enables the operation and control of two trains at the same time. It has four single-pole, double-throw switches to provide two-cab operation for four blocks. May be ganged together in any number to control additional blocks without inter-switch wiring. Can be used as area selectors for four-cab operation. Couples with #220 Controller (ATLU0220)--not provided in package. Instructions are listed on the back of the package. INCLUDES One Selector with Screws REQUIREMENTS Screwdriver