Mil-Spec AR buffer weight made of pure tungsten. 130% denser than steel. 
Weight: 1.5 oz (41 g)

Normal AR carbine buffer has 3 steel weights inside. Replacing the weights with heavier ones (tungsten) can adjust the felt recoil and cycling speed of your AR rifle. 
Heavier the buffer, slower bolt movement. 

• H1 buffer has 2 steel and 1 tungsten weight
• H2 buffer has 1 steel and 2 tungsten weights
• H3 buffer has 3 tungsten weights 

Instead of buying new buffers you can adjust them at home by replacing the weights.