Drinking Philadelphia Brewing Company’s Shackamaximum is getting a little more convenient. In years past the Kenzinger maker only issued the seasonal brew on draft, and in 22 oz. bottles. But now the dark-as-night imperial stout, which takes its name from the meeting place where William Penn signed a peace treaty with Lenni Lenape chief Tamanend, is available in 12 oz. bottles. Cases started shipping this week, and should begin popping up on the shelves at beer distributors and bottle shops in the days ahead.