Colt M4 Upper Receiver, CAGE Code marked

ships from our shop in 5 to 8 days (+/-)
Limited Availablility:
product comes in-stock every 4 to 9 months

Colt M4 Upper Receiver, CAGE Code marked

100% authentic, the real deal from Charlie's

Be careful, there are many fakes out there.  Buy from a trusted Source.  Charlie's is a Colt authorized dealer, and this part comes from Colt as a spare, or also from a new Colt rifle, for which Charlie's has disassembled.  

Factory new or new take-off, Colt upper receiver with Colt CAGE Code marked on the left side, stamped, engraved or dot peened into the side.  Some are factory new.  Most are take-offs from new guns or upper receiver groups.  Some are purchased as a part. Most have world-famous Colt oil on them.  Inside has a gray dry lube finish.  Marked M4 in the front, and with M4 feedramps.

The Colt upper receivers are not made with a "C" mark anymore, so CAGE Code marked uppers are from 2018 forward.

Note:  Colt has used, and continues to use, a number of original forgings.  These forging marks have the appearance of either a raised square, a raised keyhole, or a raised A with broken arches.  All are 100% legitimate, and your 100% Colt upper will have one of these marks.  We do not separate by forging marks, and do not take requests for forging marks.  Unfortunately, these CAGE code marked uppers are becoming very hard to get.  We are sourcing upper receivers and rifles, and looking for the CAGE code.  Most are coming without CAGE code, so our costs have gone up considerably, as we purchase in bulk and pull the CAGE code to the side.  Mostly, we are saving for our complete upper receiver builds, and as we have extras, we make available for sale.

Note:  With this Colt product, or any Colt product, expect some handling marks, oil, occasional small scratches or anodizing colors that vary.  Colt is made for battle, and in the factory, Colt parts are not treated with kid gloves.  A minor imperfection with a new or NOS Colt product is not a defect.

Includes dust cover assembly and forward assist assembly.  No BCG or charging handle.


  • 7075 high grade aluminum forging
  • Military spec hard coat anodizing
  • T-marks white painted, per milspec
  • M-4 marked and M4 feedramps
  • dry lube moly interior

Manufacturer's part number SP63528

Also note, that Charlie's stocks the same upper receiver, with different markings:

The Potomac Armory CAGE Code upper receiver

Colt unmarked upper receiver, take-off