Top of the barrel rib is marked ""A. Martin Glasgow"". Bores are smooth and .50 caliber. Barrels are 5.5"" and overall length is 10"". Pistol has captive ramrod and swivels to service each barrel. Frame, cocks, trigger guard and butt cap are all finely engraved. The butt cap opens to reveal space for two balls and or percussion caps. The stock checkering is very fine and is sharp and crisp. End of barrels have a decorative riband around the muzzle. The action works perfectly. This is a well designed self defense pistol for a gentleman!