This powder and ball, muzzle-loading, rifled airgun was made by Durs Egg between 1770 and 1800 and was probably used for hunting.

It features a swan-neck cock as found on standard firearms of the day, and comes with a rod, hand pump (that works rather like a bicycle pump) and spare butt reservoir. It would have taken up to 600 strokes of the hand pump to fill each reservoir, but this was sufficient to fire 30 lead balls: 10 at 150 yards, 10 at 120 yards, and 10 at 100 yards. This drop in range as the air pressure decreases was an issue for early airguns but many modern airguns are fitted with a regulator device which maintains a consistent velocity for every shot.

Durs Egg (1748–1831) was a Swiss-born gunmaker who established a business on the Strand, and later Pall Mall, in London. As gunmaker to the king, he had a reputation for fine-quality guns and for being at the forefront of new technologies and ideas.