An Eta-class shuttle was a used by the Dark Lord of the Sith Darth Sidious during the Clone Wars. The shuttle was not painted in the the red and white color scheme commonly seen in use by the Jedi Order, but was instead colored a nondescript gray color.
Darth Sidious' Eta-class shuttle approaches Mandalore
An Eta-class shuttle, the vessel was a drab, nondescript grey color. It was equipped with a hyperdrive that allowed the shuttle to make hyperspace jumps.
During the Clone Wars, a galaxy-spanning conflict between the Galactic Republic and the Confederacy of Independent Systems, the reigning Dark Lord of the Sith Darth Sidious learned that his former apprentice Darth Maul and his brother Savage Opress were on Mandalore, so he used this shuttle to travel to Mandalore, the Mandalorian homeworld located in the Outer Rim Territories.
The shuttle landed at the docks of the New Mandalorians' domed capital city, Sundari, where Sidious disembarked and promptly choked a pair of Mandalorian soldiers who attempted to stop him using the Force. He then proceeded from his ship into the city, leaving the shuttle at the docks.