airmail flight cover: Kohler Aviation Corporation, Milwaukee - Detroit route, 2nd Anniversary

Date:09/01/1931
Medium:Paper, ink, adhesive
Credit Line: Collection of SFO Museum
Accession Number:1999.023.007
Dimensions:4 x 6 1/2 inches (10.2 x 16.5 cm)
Collection:Aviation Archive
Category:Philately
Subcategory:Airmail Flight Cover
Description

Airmail flight cover honoring the second anniversary of the Kohler Aviation Company, Milwaukee - Detroit route; blue cachet with Kohler servicemark; signed by Chief Pilot Everett L. McMullen; postmarked September 1, 1931, Grand Rapids, Michigan over a purple 5-cent stamp; backstamp: September [illegible], 1931, Grand Rapids with football-shaped killer.

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  <a href="https://collection.sfomuseum.org/objects/1511908843/"><img src="https://static.sfomuseum.org/media/152/781/971/9/1527819719_MgRIKx2yT1nXlVZaS9lkhEYLF86K2zD1_z.jpg" alt="airmail flight cover: Kohler Aviation Corporation, Milwaukee - Detroit route, 2nd Anniversary" /></a>
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    <div><strong>Airmail flight cover: Kohler Aviation Corporation, Milwaukee - Detroit route, 2nd Anniversary</strong> 09/01/1931</div>
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    <div>Collection of SFO Museum <a href="https://collection.sfomuseum.org/objects/1511908843/">1999.023.007</a></div>
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