Cure for rheumatism!

This is a control for an electric blanket!
My father frequently went fishing with his friend who was also his Doctor. He was telling him that my Mum had been to her Doctor complaining of rheumatism. His friend Tom said the best thing would be to get her an electric blanket and advised the same one that he and his wife had, a Windak. It was so expensive they had to save up to buy it but here it is and it was still working 60 years later. Sadly FOLOH has put the actual blanket in the bin and the control will follow shortly. It weighs a stone or 7 KG for you young people! Has settings for off,low, medium and high. Also you could leave it on all night , which they did.
Recently the fire service sent men round to do a check so as we knew she had this in use, we whipped it off , into a cupboard, and replaced it after he had gone!
I can't find Windak so maybe their product was so good people never needed a new one and they went out of business!