"Stuart" wrote in message
...
I have two studio flash units that are fitted with BC lamp fittings .
These use 150W lamps as modelling lights and it seems that I am unlikely
to get 150W lamps that are thin enough in the neck to fit in the light
fitting . I have got a BC to ES adaptor which allows me to use an ES lamp
but the adaptor is marked Max 60w ,presumably because part of it is
bakelite .

If it bakelite, it is very old. Caesin based plastics started to replace
bakelite in the 1950s. However, what you want is a ceramic adaptor. I've
seen them on sale in France, but not in the UK. I suspect a web search would
be in order. Alternatively, get flash units with built-in modelling lights.

Colin Bignell