Please Help With These 2 Precancels

Good day everyone. I was checking threw my large lot of precancels and went to look at a PDF file under Ohio and noticed that there were several Dayton, Ohio. I have found 5 different stamps from Dayton. I am sure how one determines one from the other especially when not expressing size of stamp ect. on the website. I would appreciate if someone can please inform me identification of both stamps? Are these common stamps for these Bureaus?
Any information would be appreciated. Thank you in advance.

Sincerely,
Blazenstar

These are common precancels, not bureau's - the Jackson is PSS-203, Dayton PSS-204 [203 has a slightly thicker font]. This is the Dayton OH you need to search for, note the different perf spacings 10x12:

Thank you chasa appreciate to be informed about the exact identification. ..I was viewing USphila.com and they had a few of the precancels of previous auctions sold by Seigels with the precancels for the 10 x 12 (423a) with photos on them.They have a few that look like a different font size as well.
I thought I viewed a Dayton Ohio on them before.

Thank you for showing what yours look like so I will continue to search through the ones here.

Sincerely,

Blazenstar

It is so interesting. Chasa..it is definitely 10 horizontal on top. am going to get this checked about the vertical perfs on this stamp...it is definitely not a 538 with perf. 11 on the left side.

What I find so interesting about the font sizes used too.
It is important to know the difference. For example, have a font on both the St. Louis Missouri stamps one thicker than the other. The thinner one spells out Saint and the bolder font, thicker expresses St. Louis Missouri both on 1 cent green.

Thank you again for providing the photos..smiles

Blazenstar

sorry, in my first comment I meant a 424b..my mistake.smiles

11x10=538, 10x11=542,12x10=424a, 10 x 12=424b..how confused before..but this definitely correct. for the george 1 cents with certain perforations.
looking at these stamps too much.lol

Blazenstar