Hi Adam
This is Sklo because I believe sklo means glass? however it is not Sklo Union which are always pressed glass (open to correction here). I think it could be Chribska. Have you looked through the recent Chribska catalogues that Jindrich has kindly uploaded. If you look at the most recent one I think it is, there is a huge amount of information and pictures and it may be found there. I hope this helps.
m