Sorry to be pedantic.
I think what you meant to say is :
The cold shoe mount on my housing was made of plastic rather than the housing is made of plastic.
Yes, sorry I meant to say the cold shoe mount was made of plastic. I don't think its suitable for mounting a larger light and certainly not if you have an arm or two extending the light. They are very easy to crack. When mine broke Nauticam asked me to wait because they were planning to switch the cold shoe mount to metal. I waited almost a year and finally asked them the status of my replacement and I was sent another plastic mount. I suppose they decided to keep the plastic mounts. It wasn't a big deal because the M10 mount is very sturdy.