Help With US 410

I know these are best identified in pairs, but I have a single. As you can see, perfed on one side only (8 1/2 x 95 by Precision US Multigage). Also, inverted single line P watermark. Width is exactly 21 mm. Scott warns me that it is common to have fraudulently created examples from imperforates. Do I have a valid 410?

It looks trimmed on the right. I would hazard a guess that Yes, it's a trimmed large margin stamp.

If it is a perf. 8-1/2, it is a #410. The only 8-1/2 perf. for the W/Fs were coils. There were no W/Fs issued with 8-1/2 perfs. on all sides. I suppose it could be a #408 someone added perfs. to but thats unlikely. If they were trying to make a #410 from a #408 they would have made a better centered example with perfs. on both sides, and the perf. holes would be cleaner than the ones on this stamp. I believe it is a #410, just a lower quality one. I'm also thinking that this could have been dispensed from a stamp vending machine. The registration would have been off a bit causing the stamps to feed out a little out-of-line, causing the top perfs. not to come to the correct position to seperate the stamp from the roll. That is also why, I believe, the bottom is showing the entire perf. holes and a bit past them. I've seen that effect with Schermack type III and Mail-O-Meter type IV stamps used in vending machines.

Thanks for your replies. Based on the evidence, I'm going with a lower quality #410 to fill in that missing part in my collection.

Its a good filler until a better one comes along--I've plenty of them in my books. Some that may never be replaced if I don't win the lottery.