EKO Custom M4A1, 140m/s, AirsoftGuns, BY-036, BI-3681M

Professionally upgraded version EKO Custom electric airsoft guns M4A1 [BY-036/BI-3681M] with muzzle velocity up to 140 m/s. This is not a standard serial production in China or Taiwan, where it is not possible for weapons to be provided much time and care. Upgrade was provided by our company, which has more than ten years of experience and plenty of satisfied customers.

As the name suggests, it is a more economical version of the popular Custom weapons. It offers similar performance at a better price. In this variant rebarreled original motor and steel gears with the basic gear ratio. Furthermore, leaving the original placed brass cylinder and the base Spring guides with the bearing spring. Despite EKO version includes a large number of high-quality parts that are not in this price range can withstand routine and other related upgrades.

This full metal gun is supplied from the latest edition of which has recently processed metal body with functional dust cover. This is the basic model M4 with plastic handguard, tactical retractable stock (6 setting positions) and a removable transport handle, on which it is possible to attach different scopes and red dots.

Gun was fitted with favourite parts available from SHS, which has become a world leader in AEG upgrades. The following components were used..

Ventilation from the SHS:
CNC metal piston head with the bearing
SHS metal cylinder head M4
Aluminum nozzle M16/M4 - 21.5 mm

Stress parts from SHS:
Precise piston with a steel teeth

Performance parts from the SHS:
Spring M130

And the other:
Metal Hop-Up set M16/M4
Gilded T-Dean connector
Universal MOSFET switching set - type 3D

Basic metal reinforced gearbox was modified and metal chamber of gun was propped by rubber o-rings, which is intended to prevent premature rupture of the gearbox. This problem is frequent for homemade upgrade and upgraded weapons mass-produced in China or Taiwan and with strong spring. The weapon is equipped with a spring M130 and thanks to quality cylinder set and good coaxiality performance up to 140 m/s is achieved. The weapon is luxuriously equipped with low resistance wiring and silicon MOS FET switch which is absolutely necessary with strong springs, but often manufacturers and retailers underestimate. The package does not include charger or battery, we recommend to order types. See recommended accessories tab. The pack is supplied with tactical sling, sling sviwel, cleaning rod and a Wind Up Hi-cap Magazine 300 BBs.