M4/AR15 Castle Nut Tool
Available on back-order
Castle nuts on AR15s are hard to work with without proper tools. Pliers will scratch them and in some cases, you won’t be able to untighten them at all with just pliers.
That’s why this tool is handy to have at home. It’s small and fits into every toolkit.
Good to have it.
You will probably need it at some point.