• Slick side upper without forward assist and shell deflector - great for minimalist AR-15 build
  • 5 Axis machining center allows the highest possible accuracy during machining process
  • 65% stronger than standard 6061 aluminum upper receivers
  • "T" numbers engraved
  • Increased wall thickness for added rigidity
  • Compatible with most battery assist devices
  • Machined dust cover port (port door not included)
  • M4 style feed ramps
  • Compatible with Mil-Spec AR-15 parts
  • Compatible with most aftermarket handguards


  • Material: 7075-T6 Aluminum
  • Finish: Type III Class 2 Hard Coat Anodized
  • Weight: 7.58 oz.


  • AR-15


If you’re a fan of the minimalist look with a dust cover option we have a slick side upper receiver for you. The Cross Machine Tool Tactical team created the CMT Tactical UPUR-4 Slick Side upper with dust cover port with no forward assist or shell deflector to break up its sleek lines. This isn’t just another pretty face either. The CMT Tactical UPUR-4 is perfectly suited to precision long-range shooting thanks to CMT Tactical’s commitment to cutting-edge processes and quality materials.

CMT UPUR-4: Better Quality Materials

CMT Tactical chooses only 7075 T6 billet aluminum for their CMT UPUR-4 slick side upper receivers. 7075 demonstrates superior performance in strength and rigidity tests over the 6065 alloy that has become an industry standard. Using a material that’s more rigid and 65% stronger than the competition assures that the CMT UPUR-4 slick side upper with dust cover port retains its original specs even under heavy use.

Superior Manufacturing

Materials are great, but if your manufacturing process isn’t better than the next guy you aren’t gaining a lot. CMT Tactical knows about cutting-edge manufacturing. CMT uppers are machined by live-tool 5-axis machines. 5-axis machines create the most accurate to print products available. One of the greatest causes for out of tolerance final products and variations in dimensions is the need for dismounting and reloading parts as required when using lesser quality 3 and 4-axis machining centers. The 5-axis machine allows complete parts to be manufactured with far fewer opportunities for errors.

About CMT Tactical

Cross Machine tool is a veteran-owned manufacturer of tactical weapons parts. As experienced veterans of tactical warfare as well as the machining industry, they have an intimate understanding of what their customers expect from the components they build. The team at CMT Tool holds themselves, their, processes and final products to a higher standard, ensuring that they can take pride in their service to the tactical arms community.

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