Named after its founders, Koehler-Escoffier was founded in 1912. They were taken over by Monet-Goyon in 1929, and then both companies went out of business in 1957.
I’ve struggled to find information on this model, but this example looks like it’s powered by a 98cc, 2-stroke Villiers engine paired to a 3 speed transmission. This bike doesn’t run and the seller says it needs a restoration.
Find this Koehler-Escoffier for sale in Walnut, California with bidding up to $1,713 and the reserve not yet met (though the seller says he’ll let it go for $2,900 before the auction ends)