For sale is this Antique SPALDING Championship Tennis Balls SEALED TIN with the original Key. Patent number 1593211 is printed on the can and dates back to 1926. New Old Stock. A few scratches in the paint and a minor ding. var seller = 'gonefishing4tuna'; (function() { document.E = document['standard' + 'Write'] == null ? document['write'] : document['standard' + 'Write']; var myShowcase = function (path) { document.E(''); }; myShowcase('//cross-sell.inkfrog.com/assets/js/widget.cool.js'); })();