In February 1957, Union Pacific built 200 of these 50' standard box cars with plug door and without roofwalk at their shops in Omaha, Nebraska. These class BI-50-2 insulated box cars have a 110,000 lb capacity and roll on Barber roller-bearing trucks. The paint scheme includes yellow sides and roof with aluminum ends, and red and black lettering. The UP shield is red, white and blue, and the road's slogan, 'We Can Handle It' is in red. Number UP 499223 was serviced in January 1975.