A2S4000 & A2S4100
Internal Power Supply for the Apple IIc. Also called a voltage converter by some. Apple kept adding more and more shielding to them, but the one on the right seems to have a newer part number. The shielding is for the disk drive. The components on the board also changed, so maybe the necessity for shielding went away.
A) Left in photo. Astec AA7341B. Apple 699-0230. It comes with a clip on cover. May or may have the slide on cover over the top of that depending on how it comes out of the computer.
B) Right in photo. Astec AA7343A. Apple 699-0230-B. No cover or shield, as pictured.