I have a BP-26 with MPS-2 that I am selling. I’ve owned it for a few years and do not have a receipt. The manufacture date on the backside of the MPS-2 is 05/37, so I figure the warranty on that part is grandfathered in until 2025. The BP-26 has no plate or markings on it with a manufacture date.
Then, after taking another look, I found the ID plate on the underside of the BP-26. I have never seen an ID plate anywhere but on the back of a unit before. So, if you’re looking for the manufacturing date take a look at the underside.
