This 4 pack includes:

(2) Carbine Length Enhanced Buffer Springs AR15 M4
(2) Rifle Length Enhanced Buffer Springs M16

Our enhanced buffer springs are:

• Made in the USA and 100% quality inspected by hand for proper function.
  
• Constructed from certified USA made chrome silicon spring wire
• Heat treated, stress relieved
• Provides consistent spring pressure for hundreds of thousands of cycles (estimated 750,000+)
• Greater resistance to heat & high stress cyclic rates
• Improves operation, long-lasting performance
  
• Consistent pressure reduces bolt bounce
• Significantly reduces the perceived "twang" noise which is common during firing

Rifle length springs are for FULL SIZED, FIXED buttstocks.
Carbine length springs are for ADJUSTABLE buttstocks.