RealTrax bridges are designed to work with all O Gauge track systems, regardless of manufacturer.  Each bridge is fully assembled and simply mounts to the included bridge piers or can be mounted directly to scenery. Track can slide into bridge trestles and be screwed in place if desired and multiple bridges can be connected to each other using the included bridge piers to expand the bridge length. Two-track bridges are designed with sufficient gap between tracks to allow trains to pass with plenty of clearance.