W-50-1 Work Cars:
SP 11970-12219 1-2/1909 AC&F/Rodger AE 9000-9099 3/1907-12/1908 AC&F/Rodger (to SP 12990-13087) GH&SA 40300-40349 4-6/1907 AC&F/Rodger (to T&NO 40300-40349) ML&T 40350-40399 4-6/1907 AC&F/Rodger (to T&NO 40350-40399)
These work gondolas were built by AC&F/Rodger as above in 1907-1908. They featured 1040 ft3 capacity.
For more detailed information, consult Tony Thompson's book Southern Pacific Freight Cars Vol. I: Gondolas and Stock Cars.