These two handsome gentlemen are Harry Kunze, on the left, and Martin Quinn (Uncle Marty), on the right. They were my great-grandmother Molly Quinn's brother (Marty) and brother-in-law (Harry). Harry was married to Molly's younger sister Helen Quinn. Marty married Elizabeth "Bobbie" Byrnes. My sources (aka my great-uncle, Molly's son) tell me that this picture "was probably taken on Rockaway Beach or some other local beach" - local being local to the NYC area. He estimated it was taken around 1925, which would make Harry Kunze about 26, and Marty about 23. Based on the information they gave in the 1930 census, Harry and Helen would have been married for about a year.
Of course, my favorite part of this picture is the swimsuits themselves! How cool!