Found a four inch.

[john k]

Do not see four inch adjustables around here that don't have a golden price attached.   Picked up this PROTO at an antique shop,  above it is a six inch Williams,  Then 2 of the Lobster brand I have had 40 years. 

[mikeswrenches]

For what it's worth, there are at least two different shapes of the fixed jaw. The one you show that looks like a Crescent wrench and another that has a more "pointed" fixed jaw, kind of like the Lobster wrench with the red streak on it.
I'll try to get some pictures of the two.

Mike