Manchester 3312, NNB152, Leyland PD2/12 with Northern Counties H32/28R body, one of a batch of 30 delivered in 1953-1954, seen here on route 1 to Gatley on which they were regular performers.
The wide pillar to the centre of the upper deck front window was part of a ventilating system whereby the engine air intake was from the upper saloon through multiple small holes in the ceiling.

Photo taken by John Kaye, Thursday 18 August 1955, Piccadilly Bus Station, Manchester