Since Google doesn't appear to know, and it's AI makes silly guesses:
When I was small, I remember seeing hot water tanks being fitted with the "Kescocyl" brand on them. I didn't think anything of it, but hey, random memories. Recently, I pulled out an old hot water cylinder, 1975 vintage, and the old brand label fluttered down. I recognised it, and thought to look up what was on the internet; the one link that actually referred to it was an unanswered reddit post, and Google's AI (that I didn't ask for) made silly guesses that I wont repeat here!
Kescocyl is a long ago brand of Kesteven Copper Cylinders Ltd. Founded in 1972, it became a subsidiary of Glynwed International PLC. on the 31st of December 1988 (ibid) and seemingly ceased to be in 2007.
Just to follow the trail, the company that was "Glynwed International PLC." in 1989 is now Aga Rangemaster Group Limited, yes, that Aga
