In 2369, following the discovery of the Bajoran wormhole, three such vessels arrived at Deep Space 9 to begin study of it. Due to damage sustained to the station's airlocks, docking proved to be problematic, and the vessels' crews had to transport aboard. (DS9: "Emissary")
Three vessels were seen approaching the station at the climax of the episode, presumably, these were the Frunalian ships in question. The script for "Emissary" also supports this.
For more information on this design and history of this model, please see: Studio models.