12x 2-wire US-type Ground Signal _ A pack of 12 x 2-lamp plug and play signals in HO scale complete with control board and accessories. The DCD-MGS-US is a simple design 2-lamp ground signal _ the prototype for this signal dates from pre-WW2 but has not changed significantly since then. It is commonly used in the USA and other places outside Europe and the UK. It is because of this made in HO scale. In addition to its world-wide prototype use it is also a great choice of indicator signal for those with large storage or fiddle yards with a clear Red-Green indication of track access if used this way. Use as add-on for Alpha Mimic control signal systems OR use independently if you wish. Please note: If used with other power sources resistors MUST be added. (we suggest 5000 ohms or 5k resistors). Failed LEDs because of incorrect connection will not be covered by warranty.