Combat Umbrella
From Wookieepedia, the Star Wars wiki.
The Combat Umbrella was a device used by specialized clone commandos during the Clone Wars, including the members of H.O.P.E. Squad. It was used to slow descent when making high orbit precision entries such as attacking a repulsor platform.
[edit] Behind the scenes
It seems likely that the Combat Umbrella was inspired, at least in part, by the use of a similar device by the famous nanny Mary Poppins.
