Vintage milk bottle cap, MARTINS DAIRY PRODUCTS Buttermilk Washington - Union MO., unused new old stock. See pictures for condition. Size is appx. 1 5/8" in diameter. NOTE: The caps I am listing are part of my private collection which I will be selling off over the next year or two. Check back often as I am sure there will be some rare caps among these. Thank you for your purchase, I appreciate it.