The BR Ventilated Shirt was originally manufactured for the British Army for use in tropical outposts. The cotton shirt is soft and light with an intricate weave to allow breathability. Introduced in 1984 it was sold in both short and long sleeves until 1988. Interestingly, the earliest long-sleeved “Authetic British” version was made in the UK, while the short-sleeved version is imported from India. On Page 108 of Wild Company, Mel and Patricia mention contracting with the manufacturer during their first visit to the U.K. and that story is repeated in the catalog copy By 1985 the long-sleeved version is also being made in India. Toward the end of the run in 1988 they make no claims about origin, suggesting they might have gone to another, cheaper source.
The example below from my collection is one of these early U.K versions sold in 1984 . Note the large BR tag and the interesting additional yellow and pink tags in the collar.