This Anderson Tactical Replacement Bolt Knob from Pacific Tool & Gauge provides plenty of clearance for large rifle scopes and aids in faster manipulation of the bolt. The knob features a tapered body 1.25" long with an extension arm that's .75" long, resulting in an overall length of 2". Milled from aluminum and aggressively knurled for a sure grasp, the Anderson bolt knob features a 5/16"-24 thread that is compatible with PTG threaded bolt handles and Surgeon actions. Gunsmith installation may be required. Made in the USA.