The modular upper receiver block can be used in several ways for many different maintenance tasks
You may use just the lower half of the block by attaching it quickly to the upper receiver with the two provided receiver pins
This allows you to clamp the AR upper receiver to a vise for maintenance work
Bolting the two halves of the upper receiver block fully supports the upper receiver to prevent damage from torque twisting forces when installing or removing barrels from the receiver
The upper half of the block inserts into the receiver just like a bolt carrier group
The bottom half of the block can be bolted together with the upper half with the provided steel bolts
This fully supports the inside and the bottom of the receiver and it also leaves the receiver optics rail open for mounting accessories and optics
Unlike other upper receiver blocks that bolt/clamp to the exterior of the AR receiver
The upper receiver block also has a hole through the length of the block to act as a bore brush guide for cleaning out the bore of the barrel
Constructed with blue anodized Aluminum.
