Not that long ago back in November 2014 I purchased a Hoover DAM 1176 off of craigslist. I had sought after this particular model along with the very first powerdriven model (1170) since 2006 and hadn't found a single one in that 8 years except on ebay. Once I found it I instantly jumped on it because a 2nd opportunity might have not appeared in a long time. Old girl came to me very dusty but she still worked like a dream after a bag and belt was installed. I have a few questions regarding this model. Can anyone tell me the exact month and year this was produced and the month and year it was replaced by the 1178? I'm aware that it's probably a '70 or '71 model. I'm also trying to find out the exact month and year my 1176 was built. Can I find this out by the s/n? Where is the s/n located on these units? I'm seeing a # on the handle neck but I don't think it's the s/n. Can anyone also provide me with any additional info about it? I'm aware this particular model introduced the redesigned square exhaust vent and had a headlight and ridged powerdrive wheels.