Altra Phantom 166 Insert/Outsert System is purpose-built for the Phantom line of micro diameter shafts, offering superior strength and alignment. Precision-machined from 7075-T6 aluminum, the insert seats 0.875” into the shaft for maximum holding power, while the outsert threads directly onto the insert and encapsulates 0.430” of the arrow’s leading edge. This dual-lock system provides reinforced protection at the point of impact while maintaining concentricity for consistent arrow flight. Each insert comes preinstalled with a rubber O-ring, reducing vibration and securely locking the outsert in place. 

• The result is a streamlined, durable system designed to complement the Phantom’s lightweight micro diameter build and deliver reliable down-range accuracy.
   

Specifications: 

• Fitment: Fitment: Spine specific to Altra Phantom arrows
• Construction: High-grade aluminum
• Weight: 56 grains (14gr insert + 42gr outsert) 
• Quantity: 12-pack (12x inserts, 12x outserts)