DD4

This topic may not be as straight-forward as it seems.

Get an in-depth introduction to the Daniel Defense RISII, RISIII, and DD4 rail systems – From military heritage to modern modularity, you’re going to get all the details you need to build with confidence.

Trying to choose a rifle that’s the perfect fit for you? Here's an in-depth breakdown of what you need to know before you buy—so you get exactly what you’re looking for.