The Derby was built by at least three different Spanish makers, Zabala Hermanos, Francisco Sarriugarte and Armas Erbi. An American Arms brochure from 1989 says the Derby was produced in 12, 20 and 28-gauges, as well as a .410. Standard features of the single trigger model had automatic selective ejectors, fixed chokes, matted solid rib, case colored sidelock action with engraving, walnut English style straight stock and splintered forend with checkered butt. 12-ga. Derbys were available either 26" IC/M or 28" M/F. All other gauges were available only with 26" bbls. and choked IC/M. 12 and 20- ga. retailed in 1989 for $825. 28 and .410 for $859. 20/28 bi-gauge sets retailed for $1069. The double trigger version (articulated) had the same standard features and was priced ~ $40 less than the ST guns.
I have a 12-ga. 3" American Arms Derby (ZH) with 28" bbls. (opened to .010/.020) that has my duck gun since 1989. It has never failed.
