Perfect - even better than the plastic ones! - Evolution Gun Works AR Forward Assist Plug

If you're like me and you have AR upper(s) that you want no forward assist on, but your upper has the forward assist bulkhead built into it, this is the part for you. You will need a standard FA roll pin to install this, but it's self-explanatory and creates a nice, smooth look and feel for that silly bulkhead that no longer has a traditional forward assist in it.