Works well with Blackhorn 209, Pyrodex Pellets, and loose powder. A unique knurled head requires no tools for easy removal in just 3 full rotations. It incorporates a built in 209 holder. The flat face and heavy duty O-ring provide reliable ignition and reduced blow back. The Accelerator Breech Plug fits Pursuit II, Pursuit Ultralight, Vortek, Vortek Ultralight, and Buckstalker Accelerator models.