What is the value of a Diamond Arms Company Shapleigh's King Nitro 20 gauge single shot serial number 26129 xg?

The value of a Diamond Arms Company Shapleigh's King Nitro 20 gauge single shot shotgun with serial number 26129 can vary significantly based on its condition, age, and market demand. Generally, such shotguns can range from $150 to $400, with well-maintained examples or those with historical significance potentially fetching higher prices. For an accurate assessment, it's best to consult firearms appraisal experts or recent sales of similar models.