Hulme Case Feeder Picture attached.
Case feeder consists of four principal parts, the case feeder itself, the aluminum top plate which is different for different calibers (M3 works for 45 ACP and 38 Special) the case feeder cam which is attached to the tool head, and the feeder tube clamp which is attached to the top of the press. Actually there is a fifth part, the feeder tubes, (clear plastic tubes about three ft long) but they are rarely sold with the press.
Note: I have seen about four different styles of Hulme case feeders. All work on the same principal but the main steel block varies in size and shape. The one pictured is probably the most common. Most say Hulme Firearm Service on the side, but not all of them.