What do the terms O, O-27, FasTrack, RealTrax, etc. mean?
Traditional Lionel-type trains have used a 3-rail track system for over 100 years. Around 1915, Lionel introduced a new line of trains that used a gauge (distance between the rails) of 1-1/4, generally referred to as O-Gauge. Since that time there have been many variations of track that have used the common 3-rail, 1-1/4 standard. However the height and cross section of the rails, shape of the rails, and the materials used in the track all depend on the manufacturer. O-Gauge and O-27 Gauge track both use a traditional hollow steel rail mounted on steel ties and connected with steel track pins in each rail. O-Gauge is the heavy-duty version compared to O-27 Gauge track. It uses a slightly larger diameter and taller rail (about 11/16 compared to 7/16), the standard O-Gauge straight track is longer (10 to 8-3/4) and standard curve tracks make a larger circle (approximately 31 to 27). In 3-rail trains the circle diameter is usually measured from outside rail to outside rail. The 27 diamete
