Its large size distinguishes the B grill from other grilled stamps. It is 22 points high by 18 points wide (18 X 15 mm) and 'points up' in orientation when viewed from the back. The larger size of this grill may have proved a problem in production, and it was quickly replaced with smaller grills.
All four known examples of the B grill appeared on a single cover posted in Mason, Texas, in February 1869. All are denominated at three cents.
Siegel Auction Galleries Census of 3-cent Rose, B Grill (Scott 82). The Siegel Encyclopedia. http://siegelauctions.com/enc/census/82.pdf
Stevenson, William L., and Lester George Brookman. United States Grills and Notes on the Grilled Issues of the U.S. Edited by William Herzog. Triad Publications, 1980.
Notes on Grilled Issues of the United States. James Dire. http://www.jamesdire.net/grill.html