The Alcoa Aluminum Quad Hopper Car No. 6346 was produced in 1956 and is inscribed "NEW 6-56" on the sides. This SILVER painted car has BLUE lettering that shows the car number "634656," and an adhesive "ALCOA ALUMINUM" emblem on the sides. This Quad Hopper was covered and had 12 roof hatches with no center brace. It came with bar-end trucks that sometimes had tabbed couplers. There are three variations:
Variation A: With BLUE lettering as described above. The most common variation.
Variation B: With RED lettering. A rare variation.
Variation C: With BLACK lettering. A scarce variation.