Trying to answer a question from memory, I obviously made an error; and many thanks to Klaus for the correction. Krupp steel barrels fitted to a Smith gun are rare; and the examples I've seen are actually stamped "Fluid Steel-Krupp Essen-" on the bottom of each tube, and (the higher grades I've seen) engraved "Krupp Fluid Steel" atop the right barrel. Krupp barrels are common on A.H. Fox graded guns; but were only cataloged as an available option by the Hunter Arms Company from 1900-1905. I know of two Smith guns made just prior to the US entry into World War I; an Ideal 20 bore and an A2 12-bore. Maybe from animosity to Germany (?), the Krupp Steel trademark on the Ideal Grade had been over-stamped "London Steel"; and completely removed from the A-2 barrel tubes, which were then marked/labeled "Monogram Steel". Whitworth Steel barrels came standard on Smith's highest grades, but could be special ordered on lower grades down to at least Pigeon Grade quality. All Whitworth tubes came with their own unique serial number and a certificate of authenticity; but in many cases the Whitworth serial number (but not the trademark) was carded off during the barrel smoothing/finishing process.