It has a magnification strength of 2x and is one of the more common attachments seen mounted on the MX series. It has a backup red dot sight fitted above the primary optic for use in close encounters. It uses a fixed zeroing range of 300 m for the main optic, while the backup red dot sight is set to a zeroing of 200 m.
The RCO is available in either a standard matte black or green khaki finish.
- The RCO is based on the real-life "Mark 4 High Accuracy Multi-Range Riflescope" with the top mounted red dot sight being based on the "DeltaPoint Reflex Sight". Both are manufactured by Leupold Optics.