• Works with AR-15 platform rifles
• Mil-Spec carbine Buffer 
• Mil-Spec carbine spring

The SST Buffer And Spring Assembly will work well in accordance with most AR-15 platforms that also have M16, or AR-15 profile carriers. If you are using a low mass, or high mass carrier you may need to change the weight of your buffer. Most pistol caliber carbines, suppressed weapons, and certain SBR's also require different buffers.