The light will show you when the siding has live power on

operating marker lights

This is an InterMountain 4981603S HO Scale US Army GP160 with Sound #4614

This is a MTH 30-75499 O Central of Georgia RailKing Ore Car #201

Trainz Product Id: 11384145

MTH 30-74729 O Gauge Great Northern Boxcar ProductID_11441072 The light will show youThis is MTH 30 74729 O GN Boxcar. Box car, Great Northern. Car number: 34028. High quality, traditionally sized RailKing Freight Cars provide detailed bodies and colorful paint schemes for the O Gauge railroader. MTH makes an enormous variety of RailKing Freight Cars, including many different car types and roadnames. No matter what era or part of the country you are modeling, RailKing is sure to have something for you. Its key features are: