Area 419 Bolt Knob Adapter Features The Area 419 Bolt Knob Adapter is lathe spun and machined from steel then threaded to a Class 3 fit to ensure solid precise engagement with the bolt handle. This precision threading allows the adapter to convert a factory female attachment point into a standard male thread compatible with most aftermarket bolt knobs. The black nitride finish adds corrosion resistance and a durable surface that holds up to repeated handling at the range or in the field. At roughly 4.6 inches in length the adapter is sized to work cleanly with the shorter bolt handles found on modern actions. This adapter is built specifically to fit Zermatt Arms and Bighorn TL3 and Origin actions addressing a trend where action makers have moved to smaller stock in the bolt manufacturing process. Because those shorter handles often rely on female attachment points shooters have increasingly needed a reliable way to step up to a 5/16 by 24 thread for broader bolt knob compatibility. Installing this adapter opens up a wide range of aftermarket bolt knob options for improved ergonomics and faster bolt manipulation. For precision rifle shooters running a Zermatt Arms or Bighorn action this adapter is a straightforward path to a more personalized bolt setup. Area 419 Bolt Knob Adapter Specifications Manufacturer: Area 419 Model: Bolt Knob Adapter Color: Black Material: Steel Finish: Black Nitride Firearm Type: Rifle Compatible Hosts: Zermatt Arms Bighorn TL3 Bighorn Origin Thread Pattern: 5/16x24 Length: 4.6 Available At: GrabAGun