Model DCM16 - Magazine Well Dust Cover provides protection from the elements for M-16/AR-15 style rifles. Simply slip the CAMMENGA DUST COVER over the magazine well to block dust, dirt, and other problem causing contaminants. This reduces the chance of malfunctions such as jamming, and can substantially increase the life of the firearm. The CAMMENGA DUST COVER is especially useful in sandy desert environments. Model DC556M - Magazine Dust Cover provides protection from the elements for M-16/AR-15 style magazines. Simply slip the CAMMENGA MAGAZINE DUST COVER over the top opening of magazine to preserve optimal feeding performance.