Lionel O-Gauge #6812 Track Maintenance Car. The handle that turns the crank to raise/lower the platform is present and works fine (although care must be taken as it is fragile). Base number is 6511-2. Needs cleaning, but it is only surface dirt so should clean off easily. It looks like all handrails are present and in tact. This is one of the rarer dark yellow versions from 1959 and includes it's original box. Missing the two workmen figures. $30
This website has info on this car:
https://www.tandem-associates.com/lionel/lionel_trains_6812_flat_car.htm
I will be listing a number of O-Gauge train items so be sure to check out my other listings.