This is a Side mount End-of-Train Device for an HO scale train by Details West. The listing does not include the box car - only the end of train device.  This is an #1206 Red LED. Requires no more than 2.0-2.2volts 5 miliamp. One supplied 1K can be used for testing or for adding to  circuit board which is not supplied. A spplied dummy couple can make with KD scale head couplers by sliding the coupler knuckle over or use a KD coupler and drill a .032" diameter hole on the side.