Great Anik!
Not very rare piece in fact, but the label is absolutely unknown to me. Must be very old. I will try to find more about it.
I am also very pleased that Czech/Czechoslovakian/Bohemian glass has at GMB own section.
I know from collegues that GMB is read and checked by many Czech glass collectors but only few of them has such impudence to put their responses in bad English like I use to do.
Jindrich
www.cs-sklo.cz