These springs replace the original Nerf drum springs and give more consistent feeding thanks to double the pull force of the stock spring.  Great for replacing old worn out drum springs, or giving a boost to stock springs to keep up with modded full auto blasters. These do not make drums perfect.  Wide tipped darts will still be a challenge for drums due to their design especially in hot weather.  After loading drums, tap the drum a couple times to move the tips of the darts towards the front of the drum (they have a guard to keep the tips from rubbing).  This will aid in the reliability of the drums feeding. We tested the drums with Elite darts and other forms of narrow tips only.  In our testing, we could not get them to work reliably with wide tipped darts. Sold Individually.
 
Compatible with:
 
  
18 Round Drum (Requires glue to hold the spring in place)
  
25 Round Drum
  
35 Round drum