G&g m4 ras toptech full metal electric gun (tan)

new electric model semi/full auto
8mm gearbox with 1j spring installed
crane retrachable stock and 14.5 inches metal barrel
full metal casting body and monolitic ras handguard
scar type rear flip up sight
need slide stock g&p/lipo separate battery (not included)
450rd magazine included
Weight 3890 g
Length 780/970mm

Technical data:
-8mm gear box with metal bearing
-reinforced piston with steel cylinder
-steel gears and metal spring guide
-hi torque motor with long axle
-hop chamber with 363mm inner barrel