This lot has several different companies. The first 5 are marked BRUNT. Probably the most common marked tube you can find. I wish I could find the wordy Brunt and E.P.Co. tubes marked with the east liverpool address on them and the very rare B&T tubes. The next 4 are marked with the FP stylized marking which I think stands for Findlay Porcelain Co. and one marked with an F, The next two are marked U.S. for United States Porcelain Co., The two after that are marked S.P.Co. for Superior Porcelain Co., Last one is marked with two S's in diamonds for Smith & Stone Co. of Canada.