Churchkey Can Co. launched a handcrafted Pilsner-style beer in three-piece, flat-top steel cans supplied by Ball Corp. The can harkens back to the original flat-top steel beer cans that were invented in the mid-1930s and required small metal openers called church keys to open them. Made of 100 percent recyclable steel, the package is ideal for beer because it blocks light and oxygen, chills quickly and is portable, the company says.