Longines produced the Comet model in the early 1970's. 17j-cal 702, manual wind. Generally with a stainless steel case. However, there are also pictures of Comets in a gold color The dial is a mystery dial design in a two tone presentation. There were a variety of colorful dials - yellow & black, blue & black, red & black, white and black etc.. The Comet came with a leather strap or a stainless steel bracelet. I assume the coffin link bracelet was an added cost. The crown is signed with the Longines name and emblem. The Comet is a funky design that well represents the early 1970's. It is still very popular today.
From the Vintagewatchresources.com collection