A Study in Converters for other Hoovers - in Reverse Chronol
The straight brown one is original to models: 60, 61, 27 and 28.
The brown converter with the 90° bend is from a model 62
The blue one is from a 63.
Any of these three will fit any of these models: 60, 61, 62, 63, 64, 634, 27, 28...