Altra 166 Reinforced Concentric Outsert System (A.R.C.O.S.)

Altra 166 Reinforced Concentric Outsert System (A.R.C.O.S.)

Item # 1035974
Pack 12-pack


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The Pinnacle of Precision & Performance™ Altra Reinforced Concentric Outset System (A.R.C.O.S.) fits our Altra Arrows 166 Shafts and are machined out of 7075-T6 aluminum for unmatched durability and performance, with optimal fit options. 
The insert secures into the arrow shaft at a depth of 0.875", while the outsert then threads directly onto the insert and encapsulates the leading end of the arrow at 0.43" creating unmatched durability. Essential rubber O-rings come pre-installed on the insert within the A.R.C.O.S., as they aid in locking the outsert in place which reduces vibration and improves concentricity between the outsert to the insert for a more precise arrow set up and down range accuracy.

  • Accepts micro Forward Mass System (FMS) insert weights
  • Fitment:  Altra 166 shafts 250, 300, 350, & 400 spine
  • Construction: 7075-T6 aluminum 
  • Weight: 50 gr total 
  • Quantity: 12-pk