Gennert started out making their own design of view cameras, all of them made and finished as well as any Scovill or Anthony top-of-the-line camera. By about 1903, though, they were re-selling cameras from the Seneca Camera Mfg. Co. or from England. They are the only manufacturer I have yet seen that appears to have never had variations within a model (altered their model during its production run). This may be partly due to the fact that Gennert cameras are fairly rare, but I have seen probably 8-10 Burlington examples - all identical.
G.
Gennert, New York, NY
Monroe and Gennert, New York, NY
Gennert catalogs were issued until at least 1921. Prior to about 1900, Gennert had a line distinct from other manufacturers. Starting about 1901, it appears that, instead of manufacturing their own cameras, they must have purchased or contracted for cameras to me made by other manufacturers. For instance, the Eton is identical to the Anthony Compact View (Late), and the Montauk View, New Improved and New York Views are identical to Seneca View, Improved and Competitor View.
Scans of number of catalogs can be found here. Scans of Gennert catalogs are here.