That looks like a date code on the master that Chris has. Why did they make a single pot anyway? To save 15 cents a car? Of course that's the reason why they provided it to their customers.
Remember, if a accident happens as a result of a master cylinder related brake system failure, the auto company and/or the parts vendors are going to blame the motorist and/or mechanic or repair shop. The repair shop will deny responsibility along with the others since they don't know for sure who's hands we're in there.
The attorney for the plaintiffs, which would be the motorist and/or his surviving family, would have to prove it.
If the parts we're dated and tracked then he could get information on other parts, where they went into what cars and so forth. If he finds that 59 master cylinders made between may 5 1965 and may 30 1965 failed and 15 accidents happened as a result, including his clients, then if I, or any of you we're jurors we might find for the plaintiffs.
This is likely the reason for the inconsistent or missing date coding on master cylinders. The poor widow lost her case and is broke and crying with 8 kids and has nightmares of her husband screaming, "there's no brakes"!!
The fat cats are smiling as they stuff their faces at a high end steakhouse to celebrate their victory.
Where are the government regulations on brake parts? Oh right, they are too busy figuring out how to screw over the public on smog equipment.
The ability to stop a car is the most important safety item in a car, number 2 is tires, number 3 is seat belts. There have always been tire standards and tracking, funny that brakes we're overlooked. I forgot fly by wire throttles as in the case of a Japan car company. Initially they said it was the customers floor mat bunching up to the throttle pedal and recalled cars to secure the mats. Nice. Take a look at the hole in a San Diego hillside where a CHP officer was unable to stop his Japan car, he, his wife, his 12 year old daughter and his brother in law passed away in sheer terror and the japan company quietly settled on a gag order and continued to kill people in their cars.
How many families have been burned alive by a brake pedal that went to the floor and the evidence is gone because it was never there in the first place?
The attorneys can't take the case because any evidence that he would need to prove what happened is not available and he would surely lose. How many court cases involving faulty brakes and the resulting liability have there been in the last 75 years?
Tractor trailers still use asbestos, the best brake material is also the cheapest and the powerful corporations like that.
Don't believe me? Next time you drive down a grade follow one, burning asbestos smell is unmistakable as most of you "seasoned" gentleman know.