High grade custom shot guns by Fabbrica d'Armi Pietro Beretta Spa, Italy, have made special custom order over and under shotguns since the late 1960's starting with the SO3, SO4, SO5, SO6 and much latter the limited run SO9 & SO10 & side by side. Early guns were made for hunting but in time the competition models such as for Olympic Trap & Skeet were also available and won medals with the So4 & So5,with the higher grades more for exhibition and field events.The ASE & DT10 replaced the competition models ,generally, even though still available, as they had drop out leaf sprung triggers more suiting a competition environment. The guns themselves were made of special high grade metals such as the barrels in Bohler Antinit Steel and actions in chrome steel that were hand finished with screwed in side plates on each side, which then created a blank canvas for the artisan. The timber stocks are made to individual customer fit & requirements made from high grade Turkish walnut and usually oil finished. A unique feature of the guns is their side lock action and short leaf spring mechanisms which gave the user a very positive feel on closing with an accompanying sound from the barrels and extra crisp(fast)trigger pulls with some saying in the 1980's that the triggers were worth an extra 50ft/ second in cartage speed or aprox 1m less leed@ 40m, cartridge speed has improved enormously since. The models themselves evolved into different presentation grades earning the L designation and then EL and EELL depending on the engraving and craftsmanship put into them including gold inlays and later EESS which highlighted an enamel finish on the side plates.The engraving work can take years to complete before final delivery which includes the engravers name at the base of the trigger. Naturally for such exclusive shotguns the price is commensurate with the grade with new SO5 with STD finish starting (2011)@ $27,000US, to an SO6eell @ $46,000US and Over $100,000US depending upon the artisan and artwork with or without gold inlay, fretted gold crown lever etc.New or used they are always sought after and owned by some Holywood actors, depending upon the engraver(like any artist) very collectable.