Bulova 1966 Clipper

Some scratches on the glass and case. Purchased of ebay a number of years ago and rarely worn in my ownership. History of watch prior to purchase is unknown. The watch functions but likely requires a service as it does not hold time well. I believe that the watch may be a Clipper C, I don't believe that the strap is original. If you have any information of an approximate value that would be appreciated though I do not intend to sell at this time.