There isn't a lot of difference in the early Baker Gun Co. grades B, A, and Paragon. The B-grade was a $40 gun with Twist barrels, the A-grade was a $50 gun with Damascus barrels and the Paragon was a $60 gun with finer Damascus barrels.
Baker/Batavia -- Baker references are --
The Double Gun Journal -- Vol 3, Iss 3&4; Vol 9, Iss 2; and Vol 14, Iss 4 American Rifleman -- June 1968 Shooting Times -- May 1962 The Gun Report -- Nov 1989 and Jan 1991 Field & Stream -- April 1908 Guns Illustrated - 29th Edition, 1997
The Batavia guns were the low priced or "field grade" models of the Baker Gun & Forging Co. To reduce costs the Batavia line did not have the "firing pin block safety" or the "draw block" which passes transversely through the barrel lug and mates into recesses in the frame, of the graded Baker hammerless guns and the Model 1897 hammer gun. After WW-I with the rise of repeaters Baker sold their gun business to H&D Folsom Co. a major marketer, manufacturer and importer of low priced guns. Folsom added the 20-gauge to the Baker line that they produced. Folsom-made Baker guns normally have an F before or after the serial number. In the very last Baker ads that I've found in old sporting magazines from April and May 1928, and October 1929, Folsom also offered a 410-bore Batavia Leader, though I've never seen one.