I've had these bows since 1951. They came on my 1921 t touring. they fit only front seat to windshield. I'm thinking then might be runabout bows.
You are probably correct. They do appear to be runabout bows.
Square cross section and straps with windshield hooks on the front. From what I see dimension wise I'd say 1917-late 1922 approximately.
From your profile this looks like your first posting, so welcome to the forum! Since you have had your T since 1951, you probably have some good stories you can share etc. Below is an illustration posted many times on the forum. It is from the “The Model T Ford Owner” by Murray Fahnestock (available from Lang’s and other vendors and is on page 155 of the reprint see: https://www.modeltford.com/item/P9.aspx )
You can use that to see if the measurements are about the same. If you pick up any random car part in the USA from the 1920s there is a good chance it is a Ford – just because there were so many of them made compared to the other cars. But there is also the chance that it might be from one of the many other makes from back in that time frame. And many of them had similar looking but slightly different size top bows.
The roadster top will not fit a T touring front seat properly without changing the front bow or without installing the roadster top pivot in the proper place. The touring front bow attachment iron is located 36 inches from the dash and the roadster top pivot point is located 29 5/8 inches from the dash as shown in the illustration below (also Fahnestock – posted many times on the forum and on page 149 & 150 of the reprint):
The top size was the same from 1915-1922. From Bruce McCalley’s (RIP) online encyclopedia: “The bows in early 1917 were oval in cross section but were changed to rectangular cross section by 1918.” Ref: http://www.mtfca.com/encyclo/S-T.htm#top scroll down to Tops. The posting at: http://www.mtfca.com/discus/messages/118802/174633.html?1292244625 shows both oval and rectangular 1915-1922 top bows and is similar to your question.
Again welcome to the forum.
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