There are three CAIRO dairies that had embossed milk bottles. The most common (which is NOT common) is CC Sears, the second is RIDDLE and we have used a black marker to TRY to highlight the letters on this to make it easier to see. We only have pints from Riddle. The third being D.G.McGregor CAIRO is the only one known- so I guess it qualifies as rare. The Sears bottles come in half pint, pint and quart.