The only aerials that TW produced (or investigated producing) were Halos for the 2m band. For the uninitiated, a Halo is just a half wave dipole with the 'legs' bent in the shape of a circle (the ends do not meet) and is fed with coax via a gamma match . I am led to believe that Halo stands for 'HAlfwave LOop, but strictly speaking it is not a loop antenna. The Halos were intended for mobile use (horizontal polarisation) but as they were omnidirectional aerials, many people (including me) also used them as fixed station aerial. One of mine was fastened to a chimney on a 3 storey building at my original /A location in Ormskirk while the other was on the roof of my 'Moggy 1000 van' (see photo in the Introduction section).
TW 2m Halo Aerial
The 2m Halo shown below was the first version of the halo that TW introduced.
TW 2m Mini Halo Aerial
I have no real information on this aerial other than it was 6 inches in diameter and appeared in advertisements in 1964.
TWin 2m Stacked Halos
Again no real information on this aerial. It was advertised in March 1961 but it never went into production because, according to Tom Withers, during tests the TWin stacked halos exhibited a strange polar diagram and as a result their development was abandoned.