Nicknamed for the grooved pattern on the cylinder, which interacts with an arm connected to the hammer to rotate. Blade front and notch rear sights, with the top of the barrel rib marked "GEBR.MAUSER&CIE OBERNDORF A/N. WURTTEMBERG.1878.PATENT" and an oval cutout above the cylinder. Finished in a high polish blue overall, with niter blue safety catch and cylinder, and a casehardened latch and hammer. The safety latch also unlocks the large ring break lever, which controls the manual ejector. Grips are textured and checkered Gutta Percha, with raised leaf and vine designs. Matching numbers are present on the cylinder, latch and frame.

Excellent, with 90% plus of the bright original, high polish blue finish, showing scattered, minor flaking and handling marks. 85% of the correct bright niter blue finish is present on the cylinder and safety, with a brown patina forming on the remainder. Half of original case color remain on the hammer and latch, with the original pattern faded to a brown. Grips are excellent and show extremely minor handling wear. Mechanically tight, functions perfectly.