Gabriels used to make those stainless handrails on Birmingham buses and trams, the metal used to be called 'German Silver' I believe. I've seen the opened up panel-less shells of pre-war buses that have stood in a scrapyard for over 20 years, and the handrails still shine.
https://www.gabrielco.com/index.html
The anti-rattle device was a brass cylinder that was screwed to the door jamb, with a small cylinder holding a spring-loaded brass roller. This roller ran along a brass plate fitted underneath the door window (which had the 'key' symbol of the Birmingham Municipal Bank etched into the glass!) and prevented the door from rattling on its mountings. I have one in my collection of ephemera somewhere!This company supplied the doors, for those who remember the city's older trams, might recall the doors at each end which separated the motor man from the passengers. The doors were fitted with a unique anti-rattle device and a method of closure or opening, This was first introduced on the 637 class of 25 cars in 1923 and fitted to subsequent contracts are eventually fitted the older cars.
The Municipal Bank (as such) opened in October 1919, and some of the trams were older than that so it must have been a 'retrofit' in modern' speak! It is possible that not all cars had it, I have only photographs as memories.I remember the Birmingham Municipal Bank on the glass but wasn't sure that all cars had them.
I wo rked there for a few years. As a metal cutter. Previously I worked across the road from Gabriel and co. A company called I.C.E engine rebuilders. I used to do motor car cylinder reboring etc.my father worked there for years was a great place to work.I remember Gabriel’s from back in the early to mid 90s, I did some repair work to an outside tank or hopper if I recall correctly. I never went inside but I think at the time they were involved in stainless steel castings. The place sticks in my mind because while I was perched precariously on top of said tank welding, I looked up to see a blimp flying slowly overhead.