The SR-25 (Stoner Rifle-25) is a semi-automatic sniper rifle designed by Eugene Stoner and manufactured by Knight's Armament Company. The SR-25 uses a rotating bolt and a direct impingement gas system. It is loosely based on Stoner's AR-10, rebuilt in its original 7.62×51mm NATO caliber. Up to 60% of parts of the SR-25 are interchangeable with the AR-15 and M16—everything but the upper and lower receivers, the hammer, the barrel assembly and the bolt carrier group. SR-25 barrels were originally manufactured by Remington Arms with its 5R (5 grooves, rounded) rifling, with twist 1:11.25 (1 complete turn in 11.25 inches / 286 millimetres). The heavy 20 in (510 mm) barrel is free-floating, so handguards are attached to the front of the receiver and do not touch the barrel.

The SR25 airsoft gun is made of high quality ABS and metal. The contoured pistol grip, and the stock, along with the tactical front grip and RIS rail covers are made of ABS. The RIS rails, body and barrel are made from metal.

The airsoft gun has gained its maneuverability, thanks to the application of a shorter barrel and a shortened stock – with these modifications it surpasses its “long” counterpart in urban areas.   

The airsoft gun has a standard V.2 type gearbox with a longer nozzle, which greatly facilitates mounting spare parts or tuning elements. A motor with increased torque and a precision inner barrel are also fitted in this airsoft gun.

The replica is equipped with the ASCU II unit, which greatly improves the performance and overall characteristics of the gun, when compared with the standard, base model. ASCU is a two-part electronic module (a control unit and a sensor unit). The traditional switch system has been replaced by the sensor unit that monitors the current position of the sector gear, fire selector and the trigger. The information gathered by this unit is passed on to the control unit – there the software instantly analyzes the data in the processor and controls the replica's motor using a MOSFET active brake.

ASCU improves the operation of a V.2 gearbox and makes the replica comparable with the most expensive and complicated PTW-class replicas. 

The ASCU system supervises the operation of the replica regardless of the speed at which the user pulls the trigger. Furthermore, it is also responsible for the full work cycle of the piston, both during semi-automatic fire mode, and continuous fire. After each shot, the piston stops at the starting position. 

ASCU has a Low Drain Protection System specially designed to prevent damage to the lithium-polymer (LiPo) batteries.

ASCU prevents the replica from firing once it detects a problem, thereby it protects internal components from sustaining further damage.

-  The ASCU module is designed to work with other sensors which will not permit firing the replica when the magazine is empty. Moreover, the user will be compelled to use the bolt catch after the exchange of magazines, if he or she uses a replica of the „M” series.

The system improves the trigger reaction of the AEG replica, which in comparison with the classical system, is virtually instantaneous.

 The unit prevents accidental „double shots”: when the time between first and the following pull of the trigger is quicker than human reaction time - each pull of the trigger results in one shot.

- It also allows you to shoot a three-shot burst by a short pull of the trigger when in continuous fire mode.

- ASCU controls the battery charge level and prevents excessive discharge, which is crucial when using lithium batteries (LiPo, LiIon, LiFe).

- The module detects problems and defects and signals them by emitting sound and vibration. At the same time, it cuts off the power source, thus preventing more serious damage in the GB.

- This system, by cooperation with the dedicated HU chamber, eliminates blank shots in the replicas with functioning bolt catch, i.e. the shot is impossible if the magazine does not feed BBs.

- ASCU substantially increases the lifetime of the battery.

- It gives more possibilities than Systema Revolution or PTW, at much lower installation cost and allows for the use of a wide range of spare parts available for the standard V2 and V3 gearboxes.

    The set includes:

- the airsoft gun
- a magazine
- a battery
- a charger
- a tactical front grip