For Sale: a Seiko Marine Master SBBN031 in excellent condition. Asking 599 USD. Shipping is negotiable but I usually only ask for max $30 USD and cover the rest. Additional Photos: [https://imgur.com/a/E1uBYxl](https://imgur.com/a/E1uBYxl) This is an amazing watch; just not for me. The previous owner had the watch serviced in 2022 and upgraded the crystal to double-domed sapphire. The battery was also swapped out for a new one so this should be good for a few more years! Despite the watch’s size - it is a Seiko Tuna after all! - it balances well on the wrist and wears smaller than you’d think. The case and bracelet are made of titanium alloy and are quite light for a heavy duty diving watch. The watch case and crystal are in great condition. The case has some minor wear. The bracelet shows clear signs of use but is in overall good condition. The bracelet’s ratcheting system is fully functional and quite easy to use. This watch’s movement was created specifically for this model by Seiko. It is a great piece of watchmaking history and super accurate to boot! Comment before PMing to ensure a speedy response!