153) was a Polish bus brand produced by the Państwowe Zakłady Inżynieryjne (PZInż) holding between 1936 and 1937 for the city of Warsaw.

In 1936 the PZInż designed a new all-metal body for the Saurer 3CT1D and named the new bus "Zawrat" after the pass in Tatra Mountains.

However, unlike all previous wooden-built buses used or tested in Warsaw (such as Büssing 650 TU, Somua SIX or Chevrolet EFD FS 183) the Zawrat had a completely closed passenger cabin, without an open platform at the rear.

The chassis proved too rigid, making turning in the narrow streets of downtown Warsaw a difficult task.

The last surviving Zawrat (body number 53) was returned to service after the war and served in the ruined city until 1949.