The S-System has long upper rail, side rails and bottom rail that can accept both airsoft and real accessories. Rails are metal made while the system frame is plastic. The method how the S-System is locked to the gun is simple and well functional. Given the functionality of S-System battery exchange is relatively easy. Unlike in the M4 RIS this time the battery can be stored inside S-System and special wiring is provided with the gun to faciliate this. As in real SIR-system the S-System has holes across its body to allow re-positioning of rail units. Both flip up sights are fully adjustable and the rear sight is secured to low profile position with help of side lever. Similarly front flip up sight has release button to allow positioning to low profile position

As there are many people interested in the mid-level airsoft guns, and more and more "Marui Clones" and "Chinese knockoffs" are hitting the shops, I decided that AP could benefit from knowing more about them. I have been interested in the S-System and decided to pick up the BOYI version of this gun from www.airsplat.com

This is a great gun for an entry/mid level airsoft player. In comparison to Tokyo Marui, I would recommend it as a comparable alternative. It comes with all the components necessary to use it right out of the box. Two areas where I was disappointed were the plastic flash hider, and the light weight plastic butt stock. It is upgradable, but may not withstand high FPS springs.

• 330 FPS with decent rate of fire.
• Plastic receiver is a durable plastic.
• Alan type receiver pins
• Metal rails, very durable.
• Metal front and rear rifle sights
• Heavy gears. The gears seem more durable than stock Tokyo Marui gears.
• Metal hop-up chamber
• Removable sling mounts on stock and foregrip.
• Systema clone piston.
• AEG Gear box comes very well lubricated.
• Top of barrel threads off for suppressor
• Spring guide soft plastic, but it does have a aluminum base, better than stock Tokyo Marui spring guide rod.
• Metal trigger stop inside gear box (plastic on Tokyo Marui, CA, and ICS).

• Plastic flash hider comes glued on. Difficult to remove, but not impossible.
• Retractable LE style but stock is made from very light weight plastic, kind of flimsy.
• Plastic bushings. (pictures are shown with replacement metal bushings.)
• Front sight does not completely lock in the upright position, but it is pretty sturdy.
• Gear Box Cylinder is not ported. This is not always a bad thing, but with a longer barrel it can create suction and lose FPS.
• AEG Gear box is very light. May not be the best for upgrading to high velocity, not recommended for a metal piton head.
• Upper receiver is proprietary for this gun, not compatible with other AEG front ends.
• Rail system is not compatible with other guns unless custom modification