Single-action chambered for .34-, .36- or .44-caliber percussion. Half-octagon barrel from 4" to 12" in length. Centrally mounted hammer that was offset to right side to allow for sighting the pistol. Finish blued, with walnut grips. Marked, "Allen & Thurber, Allen Thurber & Company". Some specimens marked, "Allen & Wheelock". Several thousand manufactured between late 1840s and 1860.