This is our Low-Mass Carbine Buffer manufactured by Eitri’s Enhancements LLC
 
With All the Under-Gassing Solutions we sell we decided to add another item that creates a huge impact with using subsonic ammunition.
 
Reducing the weight of your buffer can increase cycling efficiency by reducing the amount of energy required to move your reciprocating mass.
 
We specifically made these for those who would rather have a quickly swappable buffer rather than modifying their own.
 
This buffer weighs 1.7oz with and uses 3 aluminum weights.
 
NOTE: These buffers only work with standard m4/mil-spec carbine buffer tubes.