Static or Accessory decoders are designed to provide control over an electrically-worked accessory like a point motor. Just like a locomotive decoder they have an address for that point to which the control handset can send instructions to change the route.
Reverse loop modules are a very useful way of avoiding short-circuits when sections of track may have opposing polarities. The outer rail going around a reverse loop will obviously start on the left and come back on the right, by isolating the track within the loop and feeding power through the module the polarity is automatically switched as the train exits the loop. This feature is useful for junctions and cross-overs, you don't need to worry about which train the electrics are set for!
Please note, we have experienced delays in the supply of these modules from all manufacturers. Please email firstname.lastname@example.org
or call us on 01453 825381 so we can check on current availability.