Various shapes and sizes of post top parking area and street lights are available in wattages ranging for 40 Watts to 100 Watts.
An example of a smaller post top that can accommodate either a 40 Watt or a 60 Watt lamp.
On the right is a comparison between a 125 Watt MV post top on the left hand side and the exact same fixture type with the 40 Watt induction lamp fitted on the right hand side.