Light All Terrain Personal Transport
From Wookieepedia, the Star Wars wiki.
The Light All Terrain Personal Transport (AT-PT) was much like the heavier AT-PT. The armor and weapons system were a step down from the original AT-PT, but was much cheaper to build. The concepts used for the AT-PT, such as the hydraulic legs and walker appearance, were the basis for the All Terrain Scout Transport (AT-ST).
