No identifying information for this gentleman, who is likely from the Bangor, Maine area. The cabinet card imprint on the front reads: Weston, Bangor. On the back it reads: F. C. Weston, Artistic Photographer, 2 Smith Block, Bangor, ME.
The photographer is likely Frank Weston, born in Maine about 1852 and listed as a photographer living in Bangor Maine in the 1900 census. 
1. 1900 U.S. census population schedule, Bangor, Penobscot County, Maine, enumeration district (ED) 76, sheet 121A, dwelling 1, family 1, Frank Weston; digital images, Ancestry (www.ancestry.com : accessed 6 February 2011); citing National Archives and Records Administration microfilm T623, roll 597.