0.16" caliber. 0.75" barrel length. SN: NSN. Bare metal finish with walnut birdshead grips. Single shot percussion black powder testing device. Item features floral scroll engraving on both flanks of the frame, and further scroll to the upper tang. The action is boxlock configuration with bordered knurling on the hammer spur. Item mounts a spring loaded dial with muzzle cover and the dial numbered from 1 to 10. Ratchet teeth engage a flat spring mounted beneath the lock. Eprouvettes, or powder testers, in this pattern were used to test the quality of gunpowder. Though various patterns had seen use as early as the 17th Century, this percussion pattern most likely dates from the mid 19th Century.