Model 2358 “Tracker” expansion boards are used with models 1833, 1835, 1837 and 1838 access controllers to expand these systems to control up to 48 entry points with a wired connection, or up to 24 entry points using a wireless connection. DKS access controllers and “tracker” expansion boards make a powerful access control combination that can be used in a variety of applications and they add many door control features to the overall system. Tracker boards are also used with DKS gate operators to provide gate operator data to the access control system.