I wanted to upgrade the handguard part of my GBB WE M4, but I wasn't really sure which handguard/barrelnut would fit it. I saw this handguard and really liked it so I just went and ordered it. Shipping was really fast, faster then I expected and when I received the part and modified my airsoft rifle I was really happy to see that the barrelnut and handguard fits perfectly on my GBB WE M4. (Note that in the attached picture it's not mounted completely on the gun yet and not aligned yet)