The middle photo appears to be an old stock and my guess would be more than 12 months folded.

Tony

@anthony-williamson 

Thanks for your input. From old threads back in 2019 some thought tubes folded for a long period would cause this.  I would have thought there would be a way to know when the tube was made. I was lucky I was going at a slow speed when the tube when down . I was able both times to stop quick enough not to damage tire or tube and see what caused loss of air. I’m just trying to figure ways to help prevent in future. Just got replacement tubes. I’m assuming with different numbers on the tube there not in the same batch. I put air in them let them sit for a day and inspected them and do not see any cracks. I think that’s all I can do , so I will install them and see how it goes. Thanks for you input.

Depending on the size you might find tubes at a farm store. I can understand Coker's position. They likely do get stock in regularly. But if they don't manufacture them, how do they know how long they are on a shelf at the manufacturer's warehouse.

I have some '29 cars and a '28. For my '29 coupe when I switched out the 50+ year old tires Kelsey Tire sent 19" tubes for my 20" tires. The tubes are labeled 19". I suspect the numbers you are looking at are the size not the date. You got 21" tubes which would be prone to having folds when mounted. A prime failure point. Make sure to use plenty of baby powder and flaps when assembling your wheels.