Unidentified Hallmark on Brandy Warmer, Please help

British Silver Reading Silver Hallmarks
1

I have a Brandy warmer with 3 Hallmarks on the bottom that I am unable to identify and I was hoping someone could help. I have been looking all over the internet, but I am at a loss.

Any info would be greatly appreciated.

Thank you
Erica
Brandi warmer markcrop.jpg